Add option to assume the best, not the worst, when cross-compiling.

Suggested by Jonas Termansen <sortie@maxsi.org>. * m4/gnulib-common.m4 (gl_COMMON_BODY): Add --enable-cross-guesses=... option. Set gl_cross_guess_normal and gl_cross_guess_inverted. * m4/argz.m4 (gl_FUNC_ARGZ): Obey --enable-cross-guesses for lt_cv_sys_argz_works. * m4/calloc.m4 (_AC_FUNC_CALLOC_IF): Obey --enable-cross-guesses for ac_cv_func_calloc_0_nonnull. * m4/canonicalize.m4 (gl_FUNC_REALPATH_WORKS): Obey --enable-cross-guesses for gl_cv_func_realpath_works. * m4/cbrtl.m4 (gl_FUNC_CBRTL): Obey --enable-cross-guesses for gl_cv_func_cbrtl_ieee. * m4/ceil.m4 (gl_FUNC_CEIL): Obey --enable-cross-guesses for gl_cv_func_ceil_ieee. * m4/ceilf.m4 (gl_FUNC_CEILF): Obey --enable-cross-guesses for gl_cv_func_ceilf_ieee. * m4/ceill.m4 (gl_FUNC_CEILL): Obey --enable-cross-guesses for gl_cv_func_ceill_ieee. * m4/chown.m4 (AC_FUNC_CHOWN): Obey --enable-cross-guesses for ac_cv_func_chown_works. (gl_FUNC_CHOWN): Obey --enable-cross-guesses for gl_cv_func_chown_slash_works, gl_cv_func_chown_ctime_works. * m4/d-ino.m4 (gl_CHECK_TYPE_STRUCT_DIRENT_D_INO): Obey --enable-cross-guesses for gl_cv_struct_dirent_d_ino. * m4/exp2l.m4 (gl_FUNC_EXP2L): Obey --enable-cross-guesses for gl_cv_func_exp2l_works, gl_cv_func_exp2l_ieee. * m4/expl.m4 (gl_FUNC_EXPL): Obey --enable-cross-guesses for gl_cv_func_expl_works. * m4/expm1.m4 (gl_FUNC_EXPM1): Obey --enable-cross-guesses for gl_cv_func_expm1_ieee. * m4/expm1l.m4 (gl_FUNC_EXPM1L): Obey --enable-cross-guesses for gl_cv_func_expm1l_works. * m4/fchdir.m4 (gl_FUNC_FCHDIR): Obey --enable-cross-guesses for gl_cv_func_open_directory_works. * m4/fchownat.m4 (gl_FUNC_FCHOWNAT_DEREF_BUG): Obey --enable-cross-guesses for gl_cv_func_fchownat_nofollow_works. (gl_FUNC_FCHOWNAT_EMPTY_FILENAME_BUG): Obey --enable-cross-guesses for gl_cv_func_fchownat_empty_filename_works. * m4/fdopendir.m4 (gl_FUNC_FDOPENDIR): Obey --enable-cross-guesses for gl_cv_func_fdopendir_works. * m4/floor.m4 (gl_FUNC_FLOOR): Obey --enable-cross-guesses for gl_cv_func_floor_ieee. * m4/floorf.m4 (gl_FUNC_FLOORF): Obey --enable-cross-guesses for gl_cv_func_floorf_ieee. * m4/fma.m4 (gl_FUNC_FMA_WORKS): Obey --enable-cross-guesses for gl_cv_func_fma_works. * m4/fmaf.m4 (gl_FUNC_FMAF_WORKS): Obey --enable-cross-guesses for gl_cv_func_fmaf_works. * m4/fmal.m4 (gl_FUNC_FMAL_WORKS): Obey --enable-cross-guesses for gl_cv_func_fmal_works. * m4/fmod.m4 (gl_FUNC_FMOD): Obey --enable-cross-guesses for gl_cv_func_fmod_ieee. * m4/fmodf.m4 (gl_FUNC_FMODF): Obey --enable-cross-guesses for gl_cv_func_fmodf_ieee. * m4/fmodl.m4 (gl_FUNC_FMODL): Obey --enable-cross-guesses for gl_cv_func_fmodl_ieee. * m4/fpurge.m4 (gl_FUNC_FPURGE): Obey --enable-cross-guesses for gl_cv_func_fpurge_works. * m4/getcwd-path-max.m4 (gl_FUNC_GETCWD_PATH_MAX): Obey --enable-cross-guesses for gl_cv_func_getcwd_path_max. * m4/getcwd.m4 (gl_FUNC_GETCWD_NULL): Obey --enable-cross-guesses for gl_cv_func_getcwd_null. (gl_FUNC_GETCWD): Update for getcwd-path-max.m4 change. * m4/getdelim.m4 (gl_FUNC_GETDELIM): Obey --enable-cross-guesses for gl_cv_func_working_getdelim. * m4/getgroups.m4 (AC_FUNC_GETGROUPS): Obey --enable-cross-guesses for ac_cv_func_getgroups_works. Keep this macro also in Autoconf >= 2.70. (gl_FUNC_GETGROUPS): Obey --enable-cross-guesses for gl_cv_func_getgroups_works. * m4/getline.m4 (gl_FUNC_GETLINE): Obey --enable-cross-guesses for am_cv_func_working_getline. * m4/getopt.m4 (gl_GETOPT_CHECK_HEADERS): Obey --enable-cross-guesses for gl_cv_func_getopt_gnu. * m4/gettimeofday.m4 (gl_FUNC_GETTIMEOFDAY_CLOBBER): Obey --enable-cross-guesses for gl_cv_func_gettimeofday_clobber. * m4/hypot.m4 (gl_FUNC_HYPOT): Obey --enable-cross-guesses for gl_cv_func_hypot_ieee. * m4/hypotf.m4 (gl_FUNC_HYPOTF): Obey --enable-cross-guesses for gl_cv_func_hypotf_ieee. * m4/hypotl.m4 (gl_FUNC_HYPOTL): Obey --enable-cross-guesses for gl_cv_func_hypotl_ieee. * m4/iconv_open-utf.m4 (gl_FUNC_ICONV_OPEN_UTF_SUPPORT): Obey --enable-cross-guesses for gl_cv_func_iconv_supports_utf. * m4/link.m4 (gl_FUNC_LINK): Obey --enable-cross-guesses for gl_cv_func_link_works. * m4/linkat.m4 (gl_FUNC_LINKAT): Obey --enable-cross-guesses for gl_cv_func_linkat_slash. * m4/log.m4 (gl_FUNC_LOG): Obey --enable-cross-guesses for gl_cv_func_log_ieee. * m4/logf.m4 (gl_FUNC_LOGF): Obey --enable-cross-guesses for gl_cv_func_logf_ieee. * m4/logl.m4 (gl_FUNC_LOGL_WORKS): Obey --enable-cross-guesses for gl_cv_func_logl_works. * m4/log10.m4 (gl_FUNC_LOG10): Obey --enable-cross-guesses for gl_cv_func_log10_ieee. * m4/log10f.m4 (gl_FUNC_LOG10F): Obey --enable-cross-guesses for gl_cv_func_log10f_ieee. * m4/log10l.m4 (gl_FUNC_LOG10L_WORKS): Obey --enable-cross-guesses for gl_cv_func_log10l_works. * m4/log1p.m4 (gl_FUNC_LOG1P): Obey --enable-cross-guesses for gl_cv_func_log1p_ieee. * m4/log1pf.m4 (gl_FUNC_LOG1PF): Obey --enable-cross-guesses for gl_cv_func_log1pf_ieee. * m4/log1pl.m4 (gl_FUNC_LOG1PL): Obey --enable-cross-guesses for gl_cv_func_log1pl_ieee. * m4/log2.m4 (gl_FUNC_LOG2): Obey --enable-cross-guesses for gl_cv_func_log2_ieee. * m4/log2f.m4 (gl_FUNC_LOG2F): Obey --enable-cross-guesses for gl_cv_func_log2f_ieee. * m4/lstat.m4 (gl_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK): Obey --enable-cross-guesses for gl_cv_func_lstat_dereferences_slashed_symlink. * m4/malloc.m4 (_AC_FUNC_MALLOC_IF): Obey --enable-cross-guesses for ac_cv_func_malloc_0_nonnull. Keep this macro also in Autoconf >= 2.70. * m4/mbrtowc.m4 (gl_MBRTOWC_C_LOCALE): Obey --enable-cross-guesses for gl_cv_C_locale_sans_EILSEQ. * m4/memchr.m4 (gl_FUNC_MEMCHR): Obey --enable-cross-guesses for gl_cv_func_memchr_works. * m4/memmem.m4 (gl_FUNC_MEMMEM_SIMPLE): Obey --enable-cross-guesses for gl_cv_func_memmem_works_always. (gl_FUNC_MEMMEM): Obey --enable-cross-guesses for gl_cv_func_memmem_works_fast. * m4/mkdir.m4 (gl_FUNC_MKDIR): Obey --enable-cross-guesses for gl_cv_func_mkdir_trailing_slash_works, gl_cv_func_mkdir_trailing_dot_works. * m4/mkfifo.m4 (gl_FUNC_MKFIFO): Obey --enable-cross-guesses for gl_cv_func_mkfifo_works. * m4/mknod.m4 (gl_FUNC_MKNOD): Obey --enable-cross-guesses for gl_cv_func_mknod_works. * m4/mkstemp.m4 (gl_FUNC_MKSTEMP): Obey --enable-cross-guesses for gl_cv_func_working_mkstemp. * m4/mktime.m4 (gl_FUNC_MKTIME_WORKS): Obey --enable-cross-guesses for gl_cv_func_working_mktime. * m4/modf.m4 (gl_FUNC_MODF): Obey --enable-cross-guesses for gl_cv_func_modf_ieee. * m4/modff.m4 (gl_FUNC_MODFF): Obey --enable-cross-guesses for gl_cv_func_modff_ieee. * m4/modfl.m4 (gl_FUNC_MODFL): Obey --enable-cross-guesses for gl_cv_func_modfl_ieee. * m4/nanosleep.m4 (gl_FUNC_NANOSLEEP): Obey --enable-cross-guesses for gl_cv_func_nanosleep. * m4/perror.m4 (gl_FUNC_PERROR): Obey --enable-cross-guesses for gl_cv_func_perror_works. * m4/printf.m4 (gl_PRINTF_SIZES_C99): Obey --enable-cross-guesses for gl_cv_func_printf_sizes_c99. (gl_PRINTF_INFINITE): Obey --enable-cross-guesses for gl_cv_func_printf_infinite. (gl_PRINTF_INFINITE_LONG_DOUBLE): Obey --enable-cross-guesses for gl_cv_func_printf_infinite_long_double. (gl_PRINTF_DIRECTIVE_A): Obey --enable-cross-guesses for gl_cv_func_printf_directive_a. (gl_PRINTF_DIRECTIVE_F): Obey --enable-cross-guesses for gl_cv_func_printf_directive_f. (gl_PRINTF_FLAG_ZERO): Obey --enable-cross-guesses for gl_cv_func_printf_flag_zero. (gl_PRINTF_ENOMEM): Obey --enable-cross-guesses for gl_cv_func_printf_enomem. (gl_SNPRINTF_TRUNCATION_C99): Obey --enable-cross-guesses for gl_cv_func_snprintf_truncation_c99. (gl_SNPRINTF_RETVAL_C99): Obey --enable-cross-guesses for gl_cv_func_snprintf_retval_c99. (gl_SNPRINTF_DIRECTIVE_N): Obey --enable-cross-guesses for gl_cv_func_snprintf_directive_n. (gl_VSNPRINTF_ZEROSIZE_C99): Obey --enable-cross-guesses for gl_cv_func_vsnprintf_zerosize_c99. * m4/pselect.m4 (gl_FUNC_PSELECT): Obey --enable-cross-guesses for gl_cv_func_pselect_detects_ebadf. * m4/pthread_rwlock_rdlock.m4 (gl_PTHREAD_RWLOCK_RDLOCK_PREFER_WRITER): Obey --enable-cross-guesses for gl_cv_pthread_rwlock_rdlock_prefer_writer. * m4/ptsname.m4 (gl_FUNC_PTSNAME): Obey --enable-cross-guesses for gl_cv_func_ptsname_sets_errno. * m4/putenv.m4 (gl_FUNC_PUTENV): Obey --enable-cross-guesses for gl_cv_func_svid_putenv. * m4/readlink.m4 (gl_FUNC_READLINK): Obey --enable-cross-guesses for gl_cv_func_readlink_works. * m4/realloc.m4 (_AC_FUNC_REALLOC_IF): Obey --enable-cross-guesses for ac_cv_func_realloc_0_nonnull. Keep this macro also in Autoconf >= 2.70. * m4/regex.m4 (gl_REGEX): Obey --enable-cross-guesses for gl_cv_func_re_compile_pattern_working. * m4/remainder.m4 (gl_FUNC_REMAINDER): Obey --enable-cross-guesses for gl_cv_func_remainder_ieee. * m4/remainderf.m4 (gl_FUNC_REMAINDERF): Obey --enable-cross-guesses for gl_cv_func_remainderf_ieee. * m4/remainderl.m4 (gl_FUNC_REMAINDERL): Obey --enable-cross-guesses for gl_cv_func_remainderl_ieee. * m4/rintl.m4 (gl_FUNC_RINTL): Obey --enable-cross-guesses for gl_cv_func_rintl_works. * m4/rmdir.m4 (gl_FUNC_RMDIR): Obey --enable-cross-guesses for gl_cv_func_rmdir_works. * m4/round.m4 (gl_FUNC_ROUND): Obey --enable-cross-guesses for gl_cv_func_round_ieee. * m4/roundf.m4 (gl_FUNC_ROUNDF): Obey --enable-cross-guesses for gl_cv_func_roundf_ieee. * m4/roundl.m4 (gl_FUNC_ROUNDL): Obey --enable-cross-guesses for gl_cv_func_roundl_ieee. * m4/select.m4 (gl_FUNC_SELECT): Obey --enable-cross-guesses for gl_cv_func_select_detects_ebadf. * m4/setenv.m4 (gl_FUNC_SETENV): Obey --enable-cross-guesses for gl_cv_func_setenv_works. (gl_FUNC_UNSETENV): Obey --enable-cross-guesses for gl_cv_func_unsetenv_works. * m4/signbit.m4 (gl_SIGNBIT): Obey --enable-cross-guesses for gl_cv_func_signbit, gl_cv_func_signbit_gcc. * m4/sleep.m4 (gl_FUNC_SLEEP): Obey --enable-cross-guesses for gl_cv_func_sleep_works. * m4/stat.m4 (gl_FUNC_STAT): Obey --enable-cross-guesses for gl_cv_func_stat_file_slash. * m4/stpncpy.m4 (gl_FUNC_STPNCPY): Obey --enable-cross-guesses for gl_cv_func_stpncpy. * m4/strcasestr.m4 (gl_FUNC_STRCASESTR_SIMPLE): Obey --enable-cross-guesses for gl_cv_func_strcasestr_works_always. (gl_FUNC_STRCASESTR): Obey --enable-cross-guesses for gl_cv_func_strcasestr_linear. * m4/strerror.m4 (gl_FUNC_STRERROR): Obey --enable-cross-guesses for gl_cv_func_working_strerror. (gl_FUNC_STRERROR_0): Obey --enable-cross-guesses for gl_cv_func_strerror_0_works. * m4/strerror_r.m4 (gl_FUNC_STRERROR_R_WORKS): Obey --enable-cross-guesses for gl_cv_func_strerror_r_works. * m4/strstr.m4 (gl_FUNC_STRSTR_SIMPLE): Obey --enable-cross-guesses for gl_cv_func_strstr_works_always. (gl_FUNC_STRSTR): Obey --enable-cross-guesses for gl_cv_func_strstr_linear. * m4/strtod.m4 (gl_FUNC_STRTOD): Obey --enable-cross-guesses for gl_cv_func_strtod_works. * m4/strtold.m4 (gl_FUNC_STRTOLD): Obey --enable-cross-guesses for gl_cv_func_strtold_works. * m4/symlink.m4 (gl_FUNC_SYMLINK): Obey --enable-cross-guesses for gl_cv_func_symlink_works. * m4/symlinkat.m4 (gl_FUNC_SYMLINKAT): Obey --enable-cross-guesses for gl_cv_func_symlinkat_works. * m4/trunc.m4 (gl_FUNC_TRUNC): Obey --enable-cross-guesses for gl_cv_func_trunc_ieee. * m4/truncf.m4 (gl_FUNC_TRUNCF): Obey --enable-cross-guesses for gl_cv_func_truncf_ieee. * m4/truncl.m4 (gl_FUNC_TRUNCL): Obey --enable-cross-guesses for gl_cv_func_truncl_ieee. * m4/tzset.m4 (gl_FUNC_TZSET_CLOBBER): Obey --enable-cross-guesses for gl_cv_func_tzset_clobber. * m4/ungetc.m4 (gl_FUNC_UNGETC_WORKS): Obey --enable-cross-guesses for gl_cv_func_ungetc_works. * m4/unlink.m4 (gl_FUNC_UNLINK): Obey --enable-cross-guesses for gl_cv_func_unlink_honors_slashes, gl_cv_func_unlink_parent_fails. * m4/usleep.m4 (gl_FUNC_USLEEP): Obey --enable-cross-guesses for gl_cv_func_usleep_works. * m4/utimens.m4 (gl_UTIMENS): Obey --enable-cross-guesses for gl_cv_func_futimesat_works. * m4/utimes.m4 (gl_FUNC_UTIMES): Obey --enable-cross-guesses for gl_cv_func_working_utimes. * m4/wcwidth.m4 (gl_FUNC_WCWIDTH): Obey --enable-cross-guesses for gl_cv_func_wcwidth_works. * m4/glob.m4 (gl_GLOB): When cross-compiling, don't create symlinks for testing. Obey --enable-cross-guesses for gl_cv_glob_lists_symlinks. * m4/rename.m4 (gl_FUNC_RENAME): When cross-compiling, don't create links for testing. Obey --enable-cross-guesses for gl_cv_func_rename_slash_dst_works, gl_cv_func_rename_slash_src_works, gl_cv_func_rename_link_works, gl_cv_func_rename_dest_works.
author: Bruno Haible <bruno@clisp.org> 2019-09-09 02:43:58 +0200
committer: Bruno Haible <bruno@clisp.org> 2019-09-09 02:43:58 +0200
commit: 84cc75b23cedfb03d0339264d46e720650b405e2 (patch)
tree: b3d374339213e790d4497fbb403164dddf641570 /m4
parent: 1c58f6921ddfd48b1b39de83999f217e22d62b94 (diff)
download: gnulib-84cc75b23cedfb03d0339264d46e720650b405e2.tar.gz
107 files changed, 452 insertions, 424 deletions
diff --git a/m4/argz.m4 b/m4/argz.m4
index b22edf251e..c0a0a637f9 100644
--- a/m4/argz.m4
+++ b/m4/argz.m4
@@ -7,7 +7,7 @@
 # unlimited permission to copy and/or distribute it, with or without
 # modifications, as long as this notice is preserved.
 
-# serial 12 argz.m4
+# serial 13 argz.m4
 
 AC_DEFUN([gl_FUNC_ARGZ],
 [gl_PREREQ_ARGZ
@@ -47,7 +47,7 @@ AS_IF([test -z "$ARGZ_H"],
          *cygwin*)
            lt_cv_sys_argz_works=no
            if test "$cross_compiling" != no; then
-             lt_cv_sys_argz_works="guessing no"
+             lt_cv_sys_argz_works="$gl_cross_guess_normal"
            else
              lt_sed_extract_leading_digits='s/^\([0-9\.]*\).*/\1/'
              save_IFS=$IFS
diff --git a/m4/calloc.m4 b/m4/calloc.m4
index d76535d804..15fb07cc43 100644
--- a/m4/calloc.m4
+++ b/m4/calloc.m4
@@ -1,4 +1,4 @@
-# calloc.m4 serial 19
+# calloc.m4 serial 20
 
 # Copyright (C) 2004-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -44,8 +44,8 @@ AC_DEFUN([_AC_FUNC_CALLOC_IF],
           *-musl*)       ac_cv_func_calloc_0_nonnull="guessing yes" ;;
                          # Guess yes on native Windows.
           mingw*)        ac_cv_func_calloc_0_nonnull="guessing yes" ;;
-                         # If we don't know, assume the worst.
-          *)             ac_cv_func_calloc_0_nonnull="guessing no" ;;
+                         # If we don't know, obey --enable-cross-guesses.
+          *)             ac_cv_func_calloc_0_nonnull="$gl_cross_guess_normal" ;;
         esac
        ])])
   case "$ac_cv_func_calloc_0_nonnull" in
diff --git a/m4/canonicalize.m4 b/m4/canonicalize.m4
index b61747bd1a..cb0896fbd8 100644
--- a/m4/canonicalize.m4
+++ b/m4/canonicalize.m4
@@ -1,4 +1,4 @@
-# canonicalize.m4 serial 30
+# canonicalize.m4 serial 31
 
 dnl Copyright (C) 2003-2007, 2009-2019 Free Software Foundation, Inc.
 
@@ -117,8 +117,8 @@ AC_DEFUN([gl_FUNC_REALPATH_WORKS],
         *-musl*)       gl_cv_func_realpath_works="guessing yes" ;;
                        # Guess no on native Windows.
         mingw*)        gl_cv_func_realpath_works="guessing no" ;;
-                       # If we don't know, assume the worst.
-        *)             gl_cv_func_realpath_works="guessing no" ;;
+                       # If we don't know, obey --enable-cross-guesses.
+        *)             gl_cv_func_realpath_works="$gl_cross_guess_normal" ;;
       esac
      ])
     rm -rf conftest.a conftest.d
diff --git a/m4/cbrtl.m4 b/m4/cbrtl.m4
index 091c7995fe..48f27da533 100644
--- a/m4/cbrtl.m4
+++ b/m4/cbrtl.m4
@@ -1,4 +1,4 @@
-# cbrtl.m4 serial 9
+# cbrtl.m4 serial 10
 dnl Copyright (C) 2012-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -78,8 +78,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_cbrtl_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_cbrtl_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_cbrtl_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_cbrtl_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/ceil.m4 b/m4/ceil.m4
index 396b3cfde0..f8b70a35f2 100644
--- a/m4/ceil.m4
+++ b/m4/ceil.m4
@@ -1,4 +1,4 @@
-# ceil.m4 serial 14
+# ceil.m4 serial 15
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -52,8 +52,8 @@ int main (int argc, char *argv[])
                *-musl*)       gl_cv_func_ceil_ieee="guessing yes" ;;
                               # Guess yes on native Windows.
                mingw*)        gl_cv_func_ceil_ieee="guessing yes" ;;
-                              # If we don't know, assume the worst.
-               *)             gl_cv_func_ceil_ieee="guessing no" ;;
+                              # If we don't know, obey --enable-cross-guesses.
+               *)             gl_cv_func_ceil_ieee="$gl_cross_guess_normal" ;;
              esac
             ])
           LIBS="$save_LIBS"
diff --git a/m4/ceilf.m4 b/m4/ceilf.m4
index 9c898b48bc..4bf2839b48 100644
--- a/m4/ceilf.m4
+++ b/m4/ceilf.m4
@@ -1,4 +1,4 @@
-# ceilf.m4 serial 18
+# ceilf.m4 serial 19
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -59,8 +59,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_ceilf_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_ceilf_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_ceilf_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_ceilf_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/ceill.m4 b/m4/ceill.m4
index a65defc30e..ff43619afb 100644
--- a/m4/ceill.m4
+++ b/m4/ceill.m4
@@ -1,4 +1,4 @@
-# ceill.m4 serial 19
+# ceill.m4 serial 20
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -58,8 +58,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_ceill_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_ceill_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_ceill_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_ceill_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/chown.m4 b/m4/chown.m4
index b693686bd9..554c492ed6 100644
--- a/m4/chown.m4
+++ b/m4/chown.m4
@@ -1,4 +1,4 @@
-# serial 33
+# serial 34
 # Determine whether we need the chown wrapper.
 
 dnl Copyright (C) 1997-2001, 2003-2005, 2007, 2009-2019 Free Software
@@ -52,8 +52,8 @@ AC_DEFUN([AC_FUNC_CHOWN],
           *-gnu* | gnu*)   ac_cv_func_chown_works="guessing yes" ;;
                            # Guess no on native Windows.
           mingw*)          ac_cv_func_chown_works="guessing no" ;;
-                           # If we don't know, assume the worst.
-          *)               ac_cv_func_chown_works="guessing no" ;;
+                           # If we don't know, obey --enable-cross-guesses.
+          *)               ac_cv_func_chown_works="$gl_cross_guess_normal" ;;
         esac
        ])
      rm -f conftest.chown
@@ -114,8 +114,8 @@ AC_DEFUN_ONCE([gl_FUNC_CHOWN],
            *-gnu*)  gl_cv_func_chown_slash_works="guessing yes" ;;
                     # Guess yes on musl systems.
            *-musl*) gl_cv_func_chown_slash_works="guessing yes" ;;
-                    # If we don't know, assume the worst.
-           *)       gl_cv_func_chown_slash_works="guessing no" ;;
+                    # If we don't know, obey --enable-cross-guesses.
+           *)       gl_cv_func_chown_slash_works="$gl_cross_guess_normal" ;;
          esac
         ])
       rm -f conftest.link conftest.file])
@@ -152,8 +152,8 @@ AC_DEFUN_ONCE([gl_FUNC_CHOWN],
            *-gnu*)  gl_cv_func_chown_ctime_works="guessing yes" ;;
                     # Guess yes on musl systems.
            *-musl*) gl_cv_func_chown_ctime_works="guessing yes" ;;
-                    # If we don't know, assume the worst.
-           *)       gl_cv_func_chown_ctime_works="guessing no" ;;
+                    # If we don't know, obey --enable-cross-guesses.
+           *)       gl_cv_func_chown_ctime_works="$gl_cross_guess_normal" ;;
          esac
         ])
       rm -f conftest.file])
diff --git a/m4/d-ino.m4 b/m4/d-ino.m4
index 87dcacc836..882fc4cb45 100644
--- a/m4/d-ino.m4
+++ b/m4/d-ino.m4
@@ -1,4 +1,4 @@
-# serial 19
+# serial 20
 
 dnl From Jim Meyering.
 dnl
@@ -46,8 +46,8 @@ AC_DEFUN([gl_CHECK_TYPE_STRUCT_DIRENT_D_INO],
               linux*-musl*) gl_cv_struct_dirent_d_ino="guessing yes" ;;
                             # Guess no on native Windows.
               mingw*)       gl_cv_struct_dirent_d_ino="guessing no" ;;
-                            # If we don't know, assume the worst.
-              *)            gl_cv_struct_dirent_d_ino="guessing no" ;;
+                            # If we don't know, obey --enable-cross-guesses.
+              *)            gl_cv_struct_dirent_d_ino="$gl_cross_guess_normal" ;;
             esac
            ])])
    case "$gl_cv_struct_dirent_d_ino" in
diff --git a/m4/exp2l.m4 b/m4/exp2l.m4
index 8bfb2d9e44..40e36bedfd 100644
--- a/m4/exp2l.m4
+++ b/m4/exp2l.m4
@@ -1,4 +1,4 @@
-# exp2l.m4 serial 8
+# exp2l.m4 serial 9
 dnl Copyright (C) 2010-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -105,8 +105,8 @@ int main (int argc, char *argv[])
                *-musl*)       gl_cv_func_exp2l_works="guessing yes" ;;
                               # Guess yes on native Windows.
                mingw*)        gl_cv_func_exp2l_works="guessing yes" ;;
-                              # If we don't know, assume the worst.
-               *)             gl_cv_func_exp2l_works="guessing no" ;;
+                              # If we don't know, obey --enable-cross-guesses.
+               *)             gl_cv_func_exp2l_works="$gl_cross_guess_normal" ;;
              esac
             ])
           LIBS="$save_LIBS"
@@ -160,8 +160,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_exp2l_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_exp2l_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_exp2l_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_exp2l_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/expl.m4 b/m4/expl.m4
index 0619a2d2ea..959dfdc70d 100644
--- a/m4/expl.m4
+++ b/m4/expl.m4
@@ -1,4 +1,4 @@
-# expl.m4 serial 14
+# expl.m4 serial 15
 dnl Copyright (C) 2010-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -175,8 +175,8 @@ int main (int argc, char *argv[])
                *-musl*)       gl_cv_func_expl_works="guessing yes" ;;
                               # Guess yes on native Windows.
                mingw*)        gl_cv_func_expl_works="guessing yes" ;;
-                              # If we don't know, assume the worst.
-               *)             gl_cv_func_expl_works="guessing no" ;;
+                              # If we don't know, obey --enable-cross-guesses.
+               *)             gl_cv_func_expl_works="$gl_cross_guess_normal" ;;
              esac
             ])
           LIBS="$save_LIBS"
diff --git a/m4/expm1.m4 b/m4/expm1.m4
index 389c7dca42..ac9b1ec7a8 100644
--- a/m4/expm1.m4
+++ b/m4/expm1.m4
@@ -1,4 +1,4 @@
-# expm1.m4 serial 8
+# expm1.m4 serial 9
 dnl Copyright (C) 2010-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -91,8 +91,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_expm1_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_expm1_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_expm1_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_expm1_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/expm1l.m4 b/m4/expm1l.m4
index 5d3a991f24..19da3f537f 100644
--- a/m4/expm1l.m4
+++ b/m4/expm1l.m4
@@ -1,4 +1,4 @@
-# expm1l.m4 serial 5
+# expm1l.m4 serial 6
 dnl Copyright (C) 2010-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -150,8 +150,8 @@ int main (int argc, char *argv[])
                *-musl*)       gl_cv_func_expm1l_works="guessing yes" ;;
                               # Guess yes on native Windows.
                mingw*)        gl_cv_func_expm1l_works="guessing yes" ;;
-                              # If we don't know, assume the worst.
-               *)             gl_cv_func_expm1l_works="guessing no" ;;
+                              # If we don't know, obey --enable-cross-guesses.
+               *)             gl_cv_func_expm1l_works="$gl_cross_guess_normal" ;;
              esac
             ])
           LIBS="$save_LIBS"
diff --git a/m4/fchdir.m4 b/m4/fchdir.m4
index ea5a4f91e9..ed295621b8 100644
--- a/m4/fchdir.m4
+++ b/m4/fchdir.m4
@@ -1,4 +1,4 @@
-# fchdir.m4 serial 24
+# fchdir.m4 serial 25
 dnl Copyright (C) 2006-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -37,8 +37,8 @@ AC_DEFUN([gl_FUNC_FCHDIR],
            *-gnu* | gnu*)   gl_cv_func_open_directory_works="guessing yes" ;;
                             # Guess no on native Windows.
            mingw*)          gl_cv_func_open_directory_works="guessing no" ;;
-                            # If we don't know, assume the worst.
-           *)               gl_cv_func_open_directory_works="guessing no" ;;
+                            # If we don't know, obey --enable-cross-guesses.
+           *)               gl_cv_func_open_directory_works="$gl_cross_guess_normal" ;;
          esac
         ])])
     case "$gl_cv_func_open_directory_works" in
diff --git a/m4/fchownat.m4 b/m4/fchownat.m4
index 042ef17ff9..f6cb409c7c 100644
--- a/m4/fchownat.m4
+++ b/m4/fchownat.m4
@@ -1,4 +1,4 @@
-# fchownat.m4 serial 4
+# fchownat.m4 serial 5
 dnl Copyright (C) 2004-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -71,7 +71,7 @@ main ()
           ]])],
        [gl_cv_func_fchownat_nofollow_works=yes],
        [gl_cv_func_fchownat_nofollow_works=no],
-       [gl_cv_func_fchownat_nofollow_works="guessing no"])
+       [gl_cv_func_fchownat_nofollow_works="$gl_cross_guess_normal"])
   ])
   AS_IF([test "$gl_cv_func_fchownat_nofollow_works" != yes], [$1], [$2])
 ])
@@ -105,7 +105,7 @@ AC_DEFUN([gl_FUNC_FCHOWNAT_EMPTY_FILENAME_BUG],
           ]])],
        [gl_cv_func_fchownat_empty_filename_works=yes],
        [gl_cv_func_fchownat_empty_filename_works=no],
-       [gl_cv_func_fchownat_empty_filename_works="guessing no"])
+       [gl_cv_func_fchownat_empty_filename_works="$gl_cross_guess_normal"])
     ])
   AS_IF([test "$gl_cv_func_fchownat_empty_filename_works" != yes], [$1], [$2])
 ])
diff --git a/m4/fdopendir.m4 b/m4/fdopendir.m4
index b2b3b03731..ad48e4ef2d 100644
--- a/m4/fdopendir.m4
+++ b/m4/fdopendir.m4
@@ -1,4 +1,4 @@
-# serial 11
+# serial 12
 # See if we need to provide fdopendir.
 
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
@@ -49,8 +49,8 @@ DIR *fdopendir (int);
             *-gnu*)  gl_cv_func_fdopendir_works="guessing yes" ;;
                      # Guess yes on musl systems.
             *-musl*) gl_cv_func_fdopendir_works="guessing yes" ;;
-                     # If we don't know, assume the worst.
-            *)       gl_cv_func_fdopendir_works="guessing no" ;;
+                     # If we don't know, obey --enable-cross-guesses.
+            *)       gl_cv_func_fdopendir_works="$gl_cross_guess_normal" ;;
           esac
          ])])
     case "$gl_cv_func_fdopendir_works" in
diff --git a/m4/floor.m4 b/m4/floor.m4
index 4bfd699622..e7de2965fe 100644
--- a/m4/floor.m4
+++ b/m4/floor.m4
@@ -1,4 +1,4 @@
-# floor.m4 serial 13
+# floor.m4 serial 14
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -48,8 +48,8 @@ int main (int argc, char *argv[])
                *-musl*)       gl_cv_func_floor_ieee="guessing yes" ;;
                               # Guess yes on native Windows.
                mingw*)        gl_cv_func_floor_ieee="guessing yes" ;;
-                              # If we don't know, assume the worst.
-               *)             gl_cv_func_floor_ieee="guessing no" ;;
+                              # If we don't know, obey --enable-cross-guesses.
+               *)             gl_cv_func_floor_ieee="$gl_cross_guess_normal" ;;
              esac
             ])
           LIBS="$save_LIBS"
diff --git a/m4/floorf.m4 b/m4/floorf.m4
index d1bd9879f8..1a2b93e996 100644
--- a/m4/floorf.m4
+++ b/m4/floorf.m4
@@ -1,4 +1,4 @@
-# floorf.m4 serial 17
+# floorf.m4 serial 18
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -55,8 +55,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_floorf_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_floorf_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_floorf_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_floorf_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/fma.m4 b/m4/fma.m4
index ac99f3cfd6..2ff3c8e080 100644
--- a/m4/fma.m4
+++ b/m4/fma.m4
@@ -1,4 +1,4 @@
-# fma.m4 serial 3
+# fma.m4 serial 4
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -169,7 +169,7 @@ int main()
         [gl_cv_func_fma_works=no],
         [dnl Guess yes on native Windows with MSVC.
          dnl Otherwise guess no, even on glibc systems.
-         gl_cv_func_fma_works="guessing no"
+         gl_cv_func_fma_works="$gl_cross_guess_normal"
          case "$host_os" in
            mingw*)
              AC_EGREP_CPP([Known], [
diff --git a/m4/fmaf.m4 b/m4/fmaf.m4
index 55edbbe027..36e0a731eb 100644
--- a/m4/fmaf.m4
+++ b/m4/fmaf.m4
@@ -1,4 +1,4 @@
-# fmaf.m4 serial 4
+# fmaf.m4 serial 5
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -173,7 +173,7 @@ int main()
         [gl_cv_func_fmaf_works=no],
         [dnl Guess yes on native Windows with MSVC.
          dnl Otherwise guess no, even on glibc systems.
-         gl_cv_func_fmaf_works="guessing no"
+         gl_cv_func_fmaf_works="$gl_cross_guess_normal"
          case "$host_os" in
            mingw*)
              AC_EGREP_CPP([Known], [
diff --git a/m4/fmal.m4 b/m4/fmal.m4
index 9ece1df0ac..76a47137ff 100644
--- a/m4/fmal.m4
+++ b/m4/fmal.m4
@@ -1,4 +1,4 @@
-# fmal.m4 serial 6
+# fmal.m4 serial 7
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -371,7 +371,7 @@ int main()
         [gl_cv_func_fmal_works=no],
         [dnl Guess yes on native Windows with MSVC.
          dnl Otherwise guess no, even on glibc systems.
-         gl_cv_func_fmal_works="guessing no"
+         gl_cv_func_fmal_works="$gl_cross_guess_normal"
          case "$host_os" in
            mingw*)
              AC_EGREP_CPP([Known], [
diff --git a/m4/fmod.m4 b/m4/fmod.m4
index cb9e568378..ae7248218d 100644
--- a/m4/fmod.m4
+++ b/m4/fmod.m4
@@ -1,4 +1,4 @@
-# fmod.m4 serial 8
+# fmod.m4 serial 9
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -64,8 +64,8 @@ int main (int argc, char *argv[])
                *-musl*)       gl_cv_func_fmod_ieee="guessing yes" ;;
                               # Guess yes on native Windows.
                mingw*)        gl_cv_func_fmod_ieee="guessing yes" ;;
-                              # If we don't know, assume the worst.
-               *)             gl_cv_func_fmod_ieee="guessing no" ;;
+                              # If we don't know, obey --enable-cross-guesses.
+               *)             gl_cv_func_fmod_ieee="$gl_cross_guess_normal" ;;
              esac
             ])
           LIBS="$save_LIBS"
diff --git a/m4/fmodf.m4 b/m4/fmodf.m4
index 7cc82f9dcd..bb6450a4aa 100644
--- a/m4/fmodf.m4
+++ b/m4/fmodf.m4
@@ -1,4 +1,4 @@
-# fmodf.m4 serial 10
+# fmodf.m4 serial 11
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -65,8 +65,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_fmodf_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_fmodf_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_fmodf_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_fmodf_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/fmodl.m4 b/m4/fmodl.m4
index 74c01ceff9..f451886a2f 100644
--- a/m4/fmodl.m4
+++ b/m4/fmodl.m4
@@ -1,4 +1,4 @@
-# fmodl.m4 serial 10
+# fmodl.m4 serial 11
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -76,8 +76,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_fmodl_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_fmodl_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_fmodl_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_fmodl_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/fpurge.m4 b/m4/fpurge.m4
index 6c5b3e97cf..d98c46903b 100644
--- a/m4/fpurge.m4
+++ b/m4/fpurge.m4
@@ -1,4 +1,4 @@
-# fpurge.m4 serial 9
+# fpurge.m4 serial 10
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -54,8 +54,8 @@ AC_DEFUN([gl_FUNC_FPURGE],
          [case "$host_os" in
                      # Guess yes on musl systems.
             *-musl*) gl_cv_func_fpurge_works="guessing yes" ;;
-                     # Guess no otherwise.
-            *)       gl_cv_func_fpurge_works="guessing no" ;;
+                     # Otherwise obey --enable-cross-guesses.
+            *)       gl_cv_func_fpurge_works="$gl_cross_guess_normal" ;;
           esac
          ])
       ])
diff --git a/m4/getcwd-path-max.m4 b/m4/getcwd-path-max.m4
index 0ae3e1e81d..95a55bef3a 100644
--- a/m4/getcwd-path-max.m4
+++ b/m4/getcwd-path-max.m4
@@ -1,4 +1,4 @@
-# serial 22
+# serial 23
 # Check for several getcwd bugs with long file names.
 # If so, arrange to compile the wrapper function.
 
@@ -220,17 +220,17 @@ main ()
        [# Cross-compilation guesses:
         case "$host_os" in
           aix*) # On AIX, it has the AIX bug.
-            gl_cv_func_getcwd_path_max='no, it has the AIX bug' ;;
+            gl_cv_func_getcwd_path_max='guessing no, it has the AIX bug' ;;
           gnu*) # On Hurd, it is 'yes'.
-            gl_cv_func_getcwd_path_max=yes ;;
+            gl_cv_func_getcwd_path_max='guessing yes' ;;
           linux* | kfreebsd*)
             # On older Linux+glibc it's 'no, but it is partly working',
             # on newer Linux+glibc it's 'yes'.
             # On Linux+musl libc, it's 'no, but it is partly working'.
             # On kFreeBSD+glibc, it's 'no, but it is partly working'.
-            gl_cv_func_getcwd_path_max='no, but it is partly working' ;;
-          *) # If we don't know, assume the worst.
-            gl_cv_func_getcwd_path_max=no ;;
+            gl_cv_func_getcwd_path_max='guessing no, but it is partly working' ;;
+          *) # If we don't know, obey --enable-cross-guesses.
+            gl_cv_func_getcwd_path_max="$gl_cross_guess_normal" ;;
         esac
        ])
     ])
diff --git a/m4/getcwd.m4 b/m4/getcwd.m4
index 625171a2fa..3b3f755458 100644
--- a/m4/getcwd.m4
+++ b/m4/getcwd.m4
@@ -6,7 +6,7 @@
 # with or without modifications, as long as this notice is preserved.
 
 # Written by Paul Eggert.
-# serial 17
+# serial 18
 
 AC_DEFUN([gl_FUNC_GETCWD_NULL],
   [
@@ -54,8 +54,8 @@ AC_DEFUN([gl_FUNC_GETCWD_NULL],
             *-musl*)       gl_cv_func_getcwd_null="guessing yes";;
                            # Guess yes on Cygwin.
             cygwin*)       gl_cv_func_getcwd_null="guessing yes";;
-                           # If we don't know, assume the worst.
-            *)             gl_cv_func_getcwd_null="guessing no";;
+                           # If we don't know, obey --enable-cross-guesses.
+            *)             gl_cv_func_getcwd_null="$gl_cross_guess_normal";;
           esac
         ]])])
 ])
@@ -127,7 +127,7 @@ AC_DEFUN([gl_FUNC_GETCWD],
   dnl Define HAVE_MINIMALLY_WORKING_GETCWD and HAVE_PARTLY_WORKING_GETCWD
   dnl if appropriate.
   case "$gl_cv_func_getcwd_path_max" in
-    "no"|"no, it has the AIX bug") ;;
+    *"no" | *"no, it has the AIX bug") ;;
     *)
       AC_DEFINE([HAVE_MINIMALLY_WORKING_GETCWD], [1],
         [Define to 1 if getcwd minimally works, that is, its result can be
@@ -135,12 +135,12 @@ AC_DEFUN([gl_FUNC_GETCWD],
       ;;
   esac
   case "$gl_cv_func_getcwd_path_max" in
-    "no, but it is partly working")
+    *"no, but it is partly working")
       AC_DEFINE([HAVE_PARTLY_WORKING_GETCWD], [1],
         [Define to 1 if getcwd works, except it sometimes fails when it
          shouldn't, setting errno to ERANGE, ENAMETOOLONG, or ENOENT.])
       ;;
-    "yes, but with shorter paths")
+    *"yes, but with shorter paths")
       AC_DEFINE([HAVE_GETCWD_SHORTER], [1],
         [Define to 1 if getcwd works, but with shorter paths
          than is generally tested with the replacement.])
diff --git a/m4/getdelim.m4 b/m4/getdelim.m4
index e77c37966c..5cd85da8b6 100644
--- a/m4/getdelim.m4
+++ b/m4/getdelim.m4
@@ -1,4 +1,4 @@
-# getdelim.m4 serial 13
+# getdelim.m4 serial 14
 
 dnl Copyright (C) 2005-2007, 2009-2019 Free Software Foundation, Inc.
 dnl
@@ -72,7 +72,7 @@ AC_DEFUN([gl_FUNC_GETDELIM],
             [gl_cv_func_working_getdelim="guessing yes"],
             [case "$host_os" in
                *-musl*) gl_cv_func_working_getdelim="guessing yes" ;;
-               *)       gl_cv_func_working_getdelim="guessing no" ;;
+               *)       gl_cv_func_working_getdelim="$gl_cross_guess_normal" ;;
              esac
             ])
          ])
diff --git a/m4/getgroups.m4 b/m4/getgroups.m4
index c93447bb11..556c177449 100644
--- a/m4/getgroups.m4
+++ b/m4/getgroups.m4
@@ -1,4 +1,4 @@
-# serial 22
+# serial 23
 
 dnl From Jim Meyering.
 dnl A wrapper around AC_FUNC_GETGROUPS.
@@ -9,8 +9,6 @@ dnl A wrapper around AC_FUNC_GETGROUPS.
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
 
-m4_version_prereq([2.70], [] ,[
-
 # This is taken from the following Autoconf patch:
 # https://git.savannah.gnu.org/gitweb/?p=autoconf.git;a=commitdiff;h=7fbb553727ed7e0e689a17594b58559ecf3ea6e9
 AC_DEFUN([AC_FUNC_GETGROUPS],
@@ -44,8 +42,8 @@ AC_DEFUN([AC_FUNC_GETGROUPS],
             *-gnu* | gnu*) ac_cv_func_getgroups_works="guessing yes" ;;
                            # Guess yes on musl systems.
             *-musl*)       ac_cv_func_getgroups_works="guessing yes" ;;
-                           # If we don't know, assume the worst.
-            *)             ac_cv_func_getgroups_works="guessing no" ;;
+                           # If we don't know, obey --enable-cross-guesses.
+            *)             ac_cv_func_getgroups_works="$gl_cross_guess_normal" ;;
           esac
          ])
       ])
@@ -61,8 +59,6 @@ AC_DEFUN([AC_FUNC_GETGROUPS],
   LIBS=$ac_save_LIBS
 ])# AC_FUNC_GETGROUPS
 
-])
-
 AC_DEFUN([gl_FUNC_GETGROUPS],
 [
   AC_REQUIRE([AC_TYPE_GETGROUPS])
@@ -99,8 +95,8 @@ AC_DEFUN([gl_FUNC_GETGROUPS],
              *-gnu* | gnu*) gl_cv_func_getgroups_works="guessing yes" ;;
                             # Guess yes on musl systems.
              *-musl*)       gl_cv_func_getgroups_works="guessing yes" ;;
-                            # If we don't know, assume the worst.
-             *)             gl_cv_func_getgroups_works="guessing no" ;;
+                            # If we don't know, obey --enable-cross-guesses.
+             *)             gl_cv_func_getgroups_works="$gl_cross_guess_normal" ;;
            esac
           ])])
       case "$gl_cv_func_getgroups_works" in
diff --git a/m4/getline.m4 b/m4/getline.m4
index 32f771c10f..457c16059a 100644
--- a/m4/getline.m4
+++ b/m4/getline.m4
@@ -1,4 +1,4 @@
-# getline.m4 serial 29
+# getline.m4 serial 30
 
 dnl Copyright (C) 1998-2003, 2005-2007, 2009-2019 Free Software Foundation,
 dnl Inc.
@@ -80,7 +80,7 @@ AC_DEFUN([gl_FUNC_GETLINE],
             [am_cv_func_working_getline="guessing yes"],
             [case "$host_os" in
                *-musl*) am_cv_func_working_getline="guessing yes" ;;
-               *)       am_cv_func_working_getline="guessing no" ;;
+               *)       am_cv_func_working_getline="$gl_cross_guess_normal" ;;
              esac
             ])
          ])
diff --git a/m4/getopt.m4 b/m4/getopt.m4
index 5991bf83e8..8cc7827873 100644
--- a/m4/getopt.m4
+++ b/m4/getopt.m4
@@ -1,4 +1,4 @@
-# getopt.m4 serial 46
+# getopt.m4 serial 47
 dnl Copyright (C) 2002-2006, 2008-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -302,8 +302,10 @@ dnl is ambiguous with environment values that contain newlines.
            ]])],
         [gl_cv_func_getopt_gnu=yes],
         [gl_cv_func_getopt_gnu=no],
-        [dnl Cross compiling. Assume the worst, even on glibc platforms.
-         gl_cv_func_getopt_gnu="guessing no"
+        [dnl Cross compiling.
+         dnl Assume the worst, even on glibc platforms.
+         dnl But obey --enable-cross-guesses.
+         gl_cv_func_getopt_gnu="$gl_cross_guess_normal"
         ])
        case $gl_had_POSIXLY_CORRECT in
          exported) ;;
diff --git a/m4/gettimeofday.m4 b/m4/gettimeofday.m4
index 5e2ef6f47e..7eebabd9c7 100644
--- a/m4/gettimeofday.m4
+++ b/m4/gettimeofday.m4
@@ -1,4 +1,4 @@
-# serial 26
+# serial 27
 
 # Copyright (C) 2001-2003, 2005, 2007, 2009-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -109,8 +109,8 @@ AC_DEFUN([gl_FUNC_GETTIMEOFDAY_CLOBBER],
         *-musl*)       gl_cv_func_gettimeofday_clobber="guessing no" ;;
                        # Guess no on native Windows.
         mingw*)        gl_cv_func_gettimeofday_clobber="guessing no" ;;
-                       # If we don't know, assume the worst.
-        *)             gl_cv_func_gettimeofday_clobber="guessing yes" ;;
+                       # If we don't know, obey --enable-cross-guesses.
+        *)             gl_cv_func_gettimeofday_clobber="$gl_cross_guess_inverted" ;;
       esac
      ])])
 
diff --git a/m4/glob.m4 b/m4/glob.m4
index 00b429722e..543722c60d 100644
--- a/m4/glob.m4
+++ b/m4/glob.m4
@@ -1,4 +1,4 @@
-# glob.m4 serial 22
+# glob.m4 serial 23
 dnl Copyright (C) 2005-2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -31,27 +31,33 @@ char a[_GNU_GLOB_INTERFACE_VERSION == 1 || _GNU_GLOB_INTERFACE_VERSION == 2 ? 1
     if test $REPLACE_GLOB = 0; then
       AC_CACHE_CHECK([whether glob lists broken symlinks],
                      [gl_cv_glob_lists_symlinks],
-        [if ln -s conf-doesntexist conf$$-globtest 2>/dev/null; then
-           gl_cv_glob_lists_symlinks=maybe
+        [if test $cross_compiling != yes; then
+           if ln -s conf-doesntexist conf$$-globtest 2>/dev/null; then
+             gl_cv_glob_lists_symlinks=maybe
+           else
+             # If we can't make a symlink, then we cannot test this issue.  Be
+             # pessimistic about this.
+             gl_cv_glob_lists_symlinks=no
+           fi
+           if test $gl_cv_glob_lists_symlinks = maybe; then
+             AC_RUN_IFELSE(
+               [AC_LANG_PROGRAM(
+                  [[#include <stddef.h>
+                    #include <glob.h>]],
+                  [[glob_t found;
+                    if (glob ("conf*-globtest", 0, NULL, &found) == GLOB_NOMATCH)
+                      return 1;
+                  ]])],
+               [gl_cv_glob_lists_symlinks=yes],
+               [gl_cv_glob_lists_symlinks=no],
+               [dnl We don't get here.
+                :
+               ])
+           fi
+           rm -f conf$$-globtest
          else
-           # If we can't make a symlink, then we cannot test this issue.  Be
-           # pessimistic about this.
-           gl_cv_glob_lists_symlinks=no
+           gl_cv_glob_lists_symlinks="$gl_cross_guess_normal"
          fi
-         if test $gl_cv_glob_lists_symlinks = maybe; then
-           AC_RUN_IFELSE(
-             [AC_LANG_PROGRAM(
-                [[#include <stddef.h>
-                  #include <glob.h>]],
-                [[glob_t found;
-                  if (glob ("conf*-globtest", 0, NULL, &found) == GLOB_NOMATCH)
-                    return 1;
-                ]])],
-             [gl_cv_glob_lists_symlinks=yes],
-             [gl_cv_glob_lists_symlinks=no],
-             [gl_cv_glob_lists_symlinks="guessing no"])
-         fi
-         rm -f conf$$-globtest
         ])
       case "$gl_cv_glob_lists_symlinks" in
         *yes) ;;
diff --git a/m4/gnulib-common.m4 b/m4/gnulib-common.m4
index 57b94ed532..ee85250f48 100644
--- a/m4/gnulib-common.m4
+++ b/m4/gnulib-common.m4
@@ -1,4 +1,4 @@
-# gnulib-common.m4 serial 44
+# gnulib-common.m4 serial 45
 dnl Copyright (C) 2007-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -115,6 +115,33 @@ AC_DEFUN([gl_COMMON_BODY], [
        errno.  */
 #define _GL_ASYNC_SAFE
 ])
+  dnl Hint which direction to take regarding cross-compilation guesses:
+  dnl When a user installs a program on a platform they are not intimately
+  dnl familiar with, --enable-cross-guesses=conservative is the appropriate
+  dnl choice.  It implements the "If we don't know, assume the worst" principle.
+  dnl However, when an operating system developer (on a platform which is not
+  dnl yet known to gnulib) builds packages for their platform, they want to
+  dnl expose, not hide, possible platform bugs; in this case,
+  dnl --enable-cross-guesses=risky is the appropriate choice.
+  dnl Sets the variables
+  dnl gl_cross_guess_normal    (to be used when 'yes' is good and 'no' is bad),
+  dnl gl_cross_guess_inverted  (to be used when 'no' is good and 'yes' is bad).
+  AC_ARG_ENABLE([cross-guesses],
+    [AS_HELP_STRING([--enable-cross-guesses={conservative|risky}],
+       [specify policy for cross-compilation guesses])],
+    [if test "x$enableval" != xconservative && test "x$enableval" != xrisky; then
+       AC_MSG_WARN([invalid argument supplied to --enable-cross-guesses])
+       enableval=conservative
+     fi
+     gl_cross_guesses="$enableval"],
+    [gl_cross_guesses=conservative])
+  if test $gl_cross_guesses = risky; then
+    gl_cross_guess_normal="guessing yes"
+    gl_cross_guess_inverted="guessing no"
+  else
+    gl_cross_guess_normal="guessing no"
+    gl_cross_guess_inverted="guessing yes"
+  fi
   dnl Preparation for running test programs:
   dnl Tell glibc to write diagnostics from -D_FORTIFY_SOURCE=2 to stderr, not
   dnl to /dev/tty, so they can be redirected to log files.  Such diagnostics
diff --git a/m4/hypot.m4 b/m4/hypot.m4
index 74448c5327..a7fb0cf430 100644
--- a/m4/hypot.m4
+++ b/m4/hypot.m4
@@ -1,4 +1,4 @@
-# hypot.m4 serial 8
+# hypot.m4 serial 9
 dnl Copyright (C) 2012-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -61,8 +61,8 @@ int main (int argc, char *argv[])
                *-musl*)       gl_cv_func_hypot_ieee="guessing yes" ;;
                               # Guess yes on native Windows.
                mingw*)        gl_cv_func_hypot_ieee="guessing yes" ;;
-                              # If we don't know, assume the worst.
-               *)             gl_cv_func_hypot_ieee="guessing no" ;;
+                              # If we don't know, obey --enable-cross-guesses.
+               *)             gl_cv_func_hypot_ieee="$gl_cross_guess_normal" ;;
              esac
             ])
           LIBS="$save_LIBS"
diff --git a/m4/hypotf.m4 b/m4/hypotf.m4
index dcdb07ac1f..550f8774cb 100644
--- a/m4/hypotf.m4
+++ b/m4/hypotf.m4
@@ -1,4 +1,4 @@
-# hypotf.m4 serial 9
+# hypotf.m4 serial 10
 dnl Copyright (C) 2012-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -77,8 +77,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_hypotf_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_hypotf_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_hypotf_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_hypotf_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/hypotl.m4 b/m4/hypotl.m4
index 3d7f47ded1..9ae1da5c10 100644
--- a/m4/hypotl.m4
+++ b/m4/hypotl.m4
@@ -1,4 +1,4 @@
-# hypotl.m4 serial 10
+# hypotl.m4 serial 11
 dnl Copyright (C) 2012-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -77,8 +77,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_hypotl_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_hypotl_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_hypotl_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_hypotl_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/iconv_open-utf.m4 b/m4/iconv_open-utf.m4
index fa60a2d084..2479f70d08 100644
--- a/m4/iconv_open-utf.m4
+++ b/m4/iconv_open-utf.m4
@@ -1,4 +1,4 @@
-# iconv_open-utf.m4 serial 3
+# iconv_open-utf.m4 serial 4
 dnl Copyright (C) 2007-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -214,7 +214,7 @@ int main ()
            dnl We know that GNU libiconv, GNU libc, musl libc, and Solaris >= 9 do.
            dnl OSF/1 5.1 has these encodings, but inserts a BOM in the "to"
            dnl direction.
-           gl_cv_func_iconv_supports_utf="guessing no"
+           gl_cv_func_iconv_supports_utf="$gl_cross_guess_normal"
            if test $gl_func_iconv_gnu = yes; then
              gl_cv_func_iconv_supports_utf="guessing yes"
            else
diff --git a/m4/link.m4 b/m4/link.m4
index a6d77b8a01..d4ab056c52 100644
--- a/m4/link.m4
+++ b/m4/link.m4
@@ -1,4 +1,4 @@
-# link.m4 serial 10
+# link.m4 serial 11
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -43,8 +43,8 @@ AC_DEFUN([gl_FUNC_LINK],
             linux-* | linux) gl_cv_func_link_works="guessing yes" ;;
                              # Guess yes on glibc systems.
             *-gnu* | gnu*)   gl_cv_func_link_works="guessing yes" ;;
-                             # If we don't know, assume the worst.
-            *)               gl_cv_func_link_works="guessing no" ;;
+                             # If we don't know, obey --enable-cross-guesses.
+            *)               gl_cv_func_link_works="$gl_cross_guess_normal" ;;
           esac
          ])
        rm -f conftest.a conftest.b conftest.lnk])
diff --git a/m4/linkat.m4 b/m4/linkat.m4
index 860abf3676..0b4ead3a32 100644
--- a/m4/linkat.m4
+++ b/m4/linkat.m4
@@ -1,4 +1,4 @@
-# serial 9
+# serial 10
 # See if we need to provide linkat replacement.
 
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
@@ -102,8 +102,8 @@ AC_DEFUN([gl_FUNC_LINKAT],
             linux-* | linux) gl_cv_func_linkat_slash="guessing yes";;
                              # Guess yes on glibc systems.
             *-gnu* | gnu*)   gl_cv_func_linkat_slash="guessing yes";;
-                             # If we don't know, assume the worst.
-            *)               gl_cv_func_linkat_slash="guessing no";;
+                             # If we don't know, obey --enable-cross-guesses.
+            *)               gl_cv_func_linkat_slash="$gl_cross_guess_normal";;
           esac
          ])
        rm -rf conftest.a conftest.b conftest.c conftest.d conftest.e conftest.s])
diff --git a/m4/log.m4 b/m4/log.m4
index 233ebe3ee2..102c0b3e3c 100644
--- a/m4/log.m4
+++ b/m4/log.m4
@@ -1,4 +1,4 @@
-# log.m4 serial 10
+# log.m4 serial 11
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -64,8 +64,8 @@ int main (int argc, char *argv[])
                *-musl*)       gl_cv_func_log_ieee="guessing yes" ;;
                               # Guess yes on native Windows.
                mingw*)        gl_cv_func_log_ieee="guessing yes" ;;
-                              # If we don't know, assume the worst.
-               *)             gl_cv_func_log_ieee="guessing no" ;;
+                              # If we don't know, obey --enable-cross-guesses.
+               *)             gl_cv_func_log_ieee="$gl_cross_guess_normal" ;;
              esac
             ])
           LIBS="$save_LIBS"
diff --git a/m4/log10.m4 b/m4/log10.m4
index e8cf74f655..e5bbfd81e4 100644
--- a/m4/log10.m4
+++ b/m4/log10.m4
@@ -1,4 +1,4 @@
-# log10.m4 serial 10
+# log10.m4 serial 11
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -64,8 +64,8 @@ int main (int argc, char *argv[])
                *-musl*)       gl_cv_func_log10_ieee="guessing yes" ;;
                               # Guess yes on native Windows.
                mingw*)        gl_cv_func_log10_ieee="guessing yes" ;;
-                              # If we don't know, assume the worst.
-               *)             gl_cv_func_log10_ieee="guessing no" ;;
+                              # If we don't know, obey --enable-cross-guesses.
+               *)             gl_cv_func_log10_ieee="$gl_cross_guess_normal" ;;
              esac
             ])
           LIBS="$save_LIBS"
diff --git a/m4/log10f.m4 b/m4/log10f.m4
index d2beeffeb8..4390f53e07 100644
--- a/m4/log10f.m4
+++ b/m4/log10f.m4
@@ -1,4 +1,4 @@
-# log10f.m4 serial 11
+# log10f.m4 serial 12
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -74,8 +74,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_log10f_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_log10f_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_log10f_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_log10f_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/log10l.m4 b/m4/log10l.m4
index ac17e76d5d..90f16425e0 100644
--- a/m4/log10l.m4
+++ b/m4/log10l.m4
@@ -1,4 +1,4 @@
-# log10l.m4 serial 7
+# log10l.m4 serial 8
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -151,8 +151,8 @@ int main (int argc, char *argv[])
            *-musl*)       gl_cv_func_log10l_works="guessing yes" ;;
                           # Guess yes on native Windows.
            mingw*)        gl_cv_func_log10l_works="guessing yes" ;;
-                          # If we don't know, assume the worst.
-           *)             gl_cv_func_log10l_works="guessing no" ;;
+                          # If we don't know, obey --enable-cross-guesses.
+           *)             gl_cv_func_log10l_works="$gl_cross_guess_normal" ;;
          esac
         ])
     ])
diff --git a/m4/log1p.m4 b/m4/log1p.m4
index 834f5c3b78..9a2f628cc9 100644
--- a/m4/log1p.m4
+++ b/m4/log1p.m4
@@ -1,4 +1,4 @@
-# log1p.m4 serial 7
+# log1p.m4 serial 8
 dnl Copyright (C) 2012-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -58,8 +58,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_log1p_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_log1p_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_log1p_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_log1p_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/log1pf.m4 b/m4/log1pf.m4
index 6cbf3fb2c4..724ede307a 100644
--- a/m4/log1pf.m4
+++ b/m4/log1pf.m4
@@ -1,4 +1,4 @@
-# log1pf.m4 serial 7
+# log1pf.m4 serial 8
 dnl Copyright (C) 2012-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -67,8 +67,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_log1pf_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_log1pf_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_log1pf_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_log1pf_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/log1pl.m4 b/m4/log1pl.m4
index baee5fca85..62bc60add4 100644
--- a/m4/log1pl.m4
+++ b/m4/log1pl.m4
@@ -1,4 +1,4 @@
-# log1pl.m4 serial 7
+# log1pl.m4 serial 8
 dnl Copyright (C) 2012-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -58,8 +58,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_log1pl_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_log1pl_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_log1pl_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_log1pl_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/log2.m4 b/m4/log2.m4
index 12abad2b1f..0b64c8b9d0 100644
--- a/m4/log2.m4
+++ b/m4/log2.m4
@@ -1,4 +1,4 @@
-# log2.m4 serial 9
+# log2.m4 serial 10
 dnl Copyright (C) 2010-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -85,8 +85,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_log2_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_log2_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_log2_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_log2_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/log2f.m4 b/m4/log2f.m4
index 22a7a67890..5df3bafc29 100644
--- a/m4/log2f.m4
+++ b/m4/log2f.m4
@@ -1,4 +1,4 @@
-# log2f.m4 serial 9
+# log2f.m4 serial 10
 dnl Copyright (C) 2010-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -86,8 +86,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_log2f_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_log2f_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_log2f_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_log2f_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/logf.m4 b/m4/logf.m4
index 178a2a7251..05d3721071 100644
--- a/m4/logf.m4
+++ b/m4/logf.m4
@@ -1,4 +1,4 @@
-# logf.m4 serial 11
+# logf.m4 serial 12
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -74,8 +74,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_logf_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_logf_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_logf_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_logf_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/logl.m4 b/m4/logl.m4
index 41106940e9..8984ec47c7 100644
--- a/m4/logl.m4
+++ b/m4/logl.m4
@@ -1,4 +1,4 @@
-# logl.m4 serial 12
+# logl.m4 serial 13
 dnl Copyright (C) 2010-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -192,8 +192,8 @@ int main (int argc, char *argv[])
            *-musl*)       gl_cv_func_logl_works="guessing yes" ;;
                           # Guess yes on native Windows.
            mingw*)        gl_cv_func_logl_works="guessing yes" ;;
-                          # If we don't know, assume the worst.
-           *)             gl_cv_func_logl_works="guessing no" ;;
+                          # If we don't know, obey --enable-cross-guesses.
+           *)             gl_cv_func_logl_works="$gl_cross_guess_normal" ;;
          esac
         ])
     ])
diff --git a/m4/lstat.m4 b/m4/lstat.m4
index ace163867e..be6d3f24b4 100644
--- a/m4/lstat.m4
+++ b/m4/lstat.m4
@@ -1,4 +1,4 @@
-# serial 32
+# serial 33
 
 # Copyright (C) 1997-2001, 2003-2019 Free Software Foundation, Inc.
 #
@@ -63,8 +63,8 @@ AC_DEFUN([gl_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK],
             # Guess no on native Windows.
             gl_cv_func_lstat_dereferences_slashed_symlink="guessing no" ;;
           *)
-            # If we don't know, assume the worst.
-            gl_cv_func_lstat_dereferences_slashed_symlink="guessing no" ;;
+            # If we don't know, obey --enable-cross-guesses.
+            gl_cv_func_lstat_dereferences_slashed_symlink="$gl_cross_guess_normal" ;;
         esac
        ])
      rm -f conftest.sym conftest.file
diff --git a/m4/malloc.m4 b/m4/malloc.m4
index c469c4508d..6555dee650 100644
--- a/m4/malloc.m4
+++ b/m4/malloc.m4
@@ -1,11 +1,9 @@
-# malloc.m4 serial 19
+# malloc.m4 serial 20
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
 
-m4_version_prereq([2.70], [] ,[
-
 # This is adapted with modifications from upstream Autoconf here:
 # https://git.savannah.gnu.org/cgit/autoconf.git/commit/?id=04be2b7a29d65d9a08e64e8e56e594c91749598c
 AC_DEFUN([_AC_FUNC_MALLOC_IF],
@@ -35,8 +33,8 @@ AC_DEFUN([_AC_FUNC_MALLOC_IF],
           *-gnu* | gnu* | *-musl* | freebsd* | netbsd* | openbsd* \
           | hpux* | solaris* | cygwin* | mingw*)
             ac_cv_func_malloc_0_nonnull="guessing yes" ;;
-          # If we don't know, assume the worst.
-          *) ac_cv_func_malloc_0_nonnull="guessing no" ;;
+          # If we don't know, obey --enable-cross-guesses.
+          *) ac_cv_func_malloc_0_nonnull="$gl_cross_guess_normal" ;;
         esac
        ])
     ])
@@ -50,8 +48,6 @@ AC_DEFUN([_AC_FUNC_MALLOC_IF],
   esac
 ])# _AC_FUNC_MALLOC_IF
 
-])
-
 # gl_FUNC_MALLOC_GNU
 # ------------------
 # Test whether 'malloc (0)' is handled like in GNU libc, and replace malloc if
diff --git a/m4/mbrtowc.m4 b/m4/mbrtowc.m4
index 4811af5d00..255e5b02a2 100644
--- a/m4/mbrtowc.m4
+++ b/m4/mbrtowc.m4
@@ -1,4 +1,4 @@
-# mbrtowc.m4 serial 31  -*- coding: utf-8 -*-
+# mbrtowc.m4 serial 32  -*- coding: utf-8 -*-
 dnl Copyright (C) 2001-2002, 2004-2005, 2008-2019 Free Software Foundation,
 dnl Inc.
 dnl This file is free software; the Free Software Foundation
@@ -599,7 +599,7 @@ AC_DEFUN([gl_MBRTOWC_C_LOCALE],
     [
      dnl Initial guess, used when cross-compiling or when no suitable locale
      dnl is present.
-     gl_cv_C_locale_sans_EILSEQ="guessing no"
+     gl_cv_C_locale_sans_EILSEQ="$gl_cross_guess_normal"
 
      AC_RUN_IFELSE(
        [AC_LANG_PROGRAM(
diff --git a/m4/memchr.m4 b/m4/memchr.m4
index 0be394db4f..c12d20ac76 100644
--- a/m4/memchr.m4
+++ b/m4/memchr.m4
@@ -1,4 +1,4 @@
-# memchr.m4 serial 14
+# memchr.m4 serial 15
 dnl Copyright (C) 2002-2004, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -94,8 +94,8 @@ AC_DEFUN_ONCE([gl_FUNC_MEMCHR],
             linux*-android*) gl_cv_func_memchr_works="guessing no" ;;
                              # Guess yes on native Windows.
             mingw*)          gl_cv_func_memchr_works="guessing yes" ;;
-                             # Be pessimistic for now.
-            *)               gl_cv_func_memchr_works="guessing no" ;;
+                             # If we don't know, obey --enable-cross-guesses.
+            *)               gl_cv_func_memchr_works="$gl_cross_guess_normal" ;;
           esac
          ])
       ])
diff --git a/m4/memmem.m4 b/m4/memmem.m4
index af2d5bbcf5..dcccefa704 100644
--- a/m4/memmem.m4
+++ b/m4/memmem.m4
@@ -1,4 +1,4 @@
-# memmem.m4 serial 25
+# memmem.m4 serial 26
 dnl Copyright (C) 2002-2004, 2007-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -68,7 +68,7 @@ AC_DEFUN([gl_FUNC_MEMMEM_SIMPLE],
 #endif
            ],
            [gl_cv_func_memmem_works_always="guessing yes"],
-           [gl_cv_func_memmem_works_always="guessing no"])
+           [gl_cv_func_memmem_works_always="$gl_cross_guess_normal"])
         ])
       ])
     case "$gl_cv_func_memmem_works_always" in
@@ -138,7 +138,7 @@ static void quit (int sig) { _exit (sig + 128); }
 #endif
            ],
            [gl_cv_func_memmem_works_fast="guessing yes"],
-           [gl_cv_func_memmem_works_fast="guessing no"])
+           [gl_cv_func_memmem_works_fast="$gl_cross_guess_normal"])
         ])
       ])
     case "$gl_cv_func_memmem_works_fast" in
diff --git a/m4/mkdir.m4 b/m4/mkdir.m4
index 366a3cd744..6451fb7248 100644
--- a/m4/mkdir.m4
+++ b/m4/mkdir.m4
@@ -1,4 +1,4 @@
-# serial 15
+# serial 16
 
 # Copyright (C) 2001, 2003-2004, 2006, 2008-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -36,8 +36,8 @@ AC_DEFUN([gl_FUNC_MKDIR],
                             [gl_cv_func_mkdir_trailing_slash_works="guessing yes"],
                             [gl_cv_func_mkdir_trailing_slash_works="guessing no"])
                           ;;
-                          # If we don't know, assume the worst.
-         *)               gl_cv_func_mkdir_trailing_slash_works="guessing no" ;;
+                          # If we don't know, obey --enable-cross-guesses.
+         *)               gl_cv_func_mkdir_trailing_slash_works="$gl_cross_guess_normal" ;;
        esac
       ])
     rm -rf conftest.dir
@@ -66,8 +66,8 @@ AC_DEFUN([gl_FUNC_MKDIR],
          *-musl*)       gl_cv_func_mkdir_trailing_dot_works="guessing yes" ;;
                         # Guess no on native Windows.
          mingw*)        gl_cv_func_mkdir_trailing_dot_works="guessing no" ;;
-                        # If we don't know, assume the worst.
-         *)             gl_cv_func_mkdir_trailing_dot_works="guessing no" ;;
+                        # If we don't know, obey --enable-cross-guesses.
+         *)             gl_cv_func_mkdir_trailing_dot_works="$gl_cross_guess_normal" ;;
        esac
       ])
     rm -rf conftest.dir
diff --git a/m4/mkfifo.m4 b/m4/mkfifo.m4
index 37a6fc70d3..f0c14d2ccb 100644
--- a/m4/mkfifo.m4
+++ b/m4/mkfifo.m4
@@ -1,4 +1,4 @@
-# serial 8
+# serial 9
 # See if we need to provide mkfifo replacement.
 
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
@@ -56,8 +56,8 @@ AC_DEFUN([gl_FUNC_MKFIFO],
             linux-* | linux) gl_cv_func_mkfifo_works="guessing yes" ;;
                              # Guess yes on glibc systems.
             *-gnu* | gnu*)   gl_cv_func_mkfifo_works="guessing yes" ;;
-                             # If we don't know, assume the worst.
-            *)               gl_cv_func_mkfifo_works="guessing no" ;;
+                             # If we don't know, obey --enable-cross-guesses.
+            *)               gl_cv_func_mkfifo_works="$gl_cross_guess_normal" ;;
           esac
          ])
        rm -f conftest.tmp conftest.lnk])
diff --git a/m4/mknod.m4 b/m4/mknod.m4
index 710784d05f..691cf6a1e1 100644
--- a/m4/mknod.m4
+++ b/m4/mknod.m4
@@ -1,4 +1,4 @@
-# serial 7
+# serial 8
 # See if we need to provide mknod replacement.
 
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
@@ -47,8 +47,8 @@ AC_DEFUN([gl_FUNC_MKNOD],
             linux-* | linux) gl_cv_func_mknod_works="guessing yes" ;;
                              # Guess yes on glibc systems.
             *-gnu* | gnu*)   gl_cv_func_mknod_works="guessing yes" ;;
-                             # If we don't know, assume the worst.
-            *)               gl_cv_func_mknod_works="guessing no" ;;
+                             # If we don't know, obey --enable-cross-guesses.
+            *)               gl_cv_func_mknod_works="$gl_cross_guess_normal" ;;
           esac
          ])
        rm -f conftest.fifo])
diff --git a/m4/mkstemp.m4 b/m4/mkstemp.m4
index 1b15c2eb3a..45f79fa4e0 100644
--- a/m4/mkstemp.m4
+++ b/m4/mkstemp.m4
@@ -1,4 +1,4 @@
-#serial 26
+#serial 27
 
 # Copyright (C) 2001, 2003-2007, 2009-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -63,8 +63,8 @@ AC_DEFUN([gl_FUNC_MKSTEMP],
              *-musl*)       gl_cv_func_working_mkstemp="guessing yes" ;;
                             # Guess no on native Windows.
              mingw*)        gl_cv_func_working_mkstemp="guessing no" ;;
-                            # If we don't know, assume the worst.
-             *)             gl_cv_func_working_mkstemp="guessing no" ;;
+                            # If we don't know, obey --enable-cross-guesses.
+             *)             gl_cv_func_working_mkstemp="$gl_cross_guess_normal" ;;
            esac
           ])
         rm -rf conftest.mkstemp
diff --git a/m4/mktime.m4 b/m4/mktime.m4
index a86e1eebc6..405476145c 100644
--- a/m4/mktime.m4
+++ b/m4/mktime.m4
@@ -1,4 +1,4 @@
-# serial 30
+# serial 31
 dnl Copyright (C) 2002-2003, 2005-2007, 2009-2019 Free Software Foundation,
 dnl Inc.
 dnl This file is free software; the Free Software Foundation
@@ -247,7 +247,7 @@ main ()
        [case "$host_os" in
                   # Guess no on native Windows.
           mingw*) gl_cv_func_working_mktime="guessing no" ;;
-          *)      gl_cv_func_working_mktime="guessing no" ;;
+          *)      gl_cv_func_working_mktime="$gl_cross_guess_normal" ;;
         esac
        ])
     ])
diff --git a/m4/modf.m4 b/m4/modf.m4
index 3b4b7f1d69..7bd295d032 100644
--- a/m4/modf.m4
+++ b/m4/modf.m4
@@ -1,4 +1,4 @@
-# modf.m4 serial 7
+# modf.m4 serial 8
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -74,8 +74,8 @@ int main (int argc, char *argv[])
                                 [gl_cv_func_modf_ieee="guessing yes"],
                                 [gl_cv_func_modf_ieee="guessing no"])
                               ;;
-                              # If we don't know, assume the worst.
-               *)             gl_cv_func_modf_ieee="guessing no" ;;
+                              # If we don't know, obey --enable-cross-guesses.
+               *)             gl_cv_func_modf_ieee="$gl_cross_guess_normal" ;;
              esac
             ])
           LIBS="$save_LIBS"
diff --git a/m4/modff.m4 b/m4/modff.m4
index 44ce838ee7..815ae69806 100644
--- a/m4/modff.m4
+++ b/m4/modff.m4
@@ -1,4 +1,4 @@
-# modff.m4 serial 9
+# modff.m4 serial 10
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -82,8 +82,8 @@ int main (int argc, char *argv[])
                                   [gl_cv_func_modff_ieee="guessing yes"],
                                   [gl_cv_func_modff_ieee="guessing no"])
                                 ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_modff_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_modff_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/modfl.m4 b/m4/modfl.m4
index 2859c4d2e7..ee9d6afeec 100644
--- a/m4/modfl.m4
+++ b/m4/modfl.m4
@@ -1,4 +1,4 @@
-# modfl.m4 serial 7
+# modfl.m4 serial 8
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -76,8 +76,8 @@ int main (int argc, char *argv[])
                                   [gl_cv_func_modfl_ieee="guessing yes"],
                                   [gl_cv_func_modfl_ieee="guessing no"])
                                 ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_modfl_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_modfl_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/nanosleep.m4 b/m4/nanosleep.m4
index 971aae329f..012279fab0 100644
--- a/m4/nanosleep.m4
+++ b/m4/nanosleep.m4
@@ -1,4 +1,4 @@
-# serial 38
+# serial 39
 
 dnl From Jim Meyering.
 dnl Check for the nanosleep function.
@@ -119,8 +119,8 @@ AC_DEFUN([gl_FUNC_NANOSLEEP],
             gl_cv_func_nanosleep='guessing no (mishandles large arguments)' ;;
           mingw*) # Guess no on native Windows.
             gl_cv_func_nanosleep='guessing no' ;;
-          *)      # If we don't know, assume the worst.
-            gl_cv_func_nanosleep='guessing no' ;;
+          *)      # If we don't know, obey --enable-cross-guesses.
+            gl_cv_func_nanosleep="$gl_cross_guess_normal" ;;
         esac
        ])
     ])
diff --git a/m4/perror.m4 b/m4/perror.m4
index 08e2db187b..8e9a3a8e97 100644
--- a/m4/perror.m4
+++ b/m4/perror.m4
@@ -1,4 +1,4 @@
-# perror.m4 serial 8
+# perror.m4 serial 9
 dnl Copyright (C) 2008-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -52,8 +52,8 @@ AC_DEFUN([gl_FUNC_PERROR],
               *-musl*) gl_cv_func_perror_works="guessing yes" ;;
                        # Guess yes on native Windows.
               mingw*)  gl_cv_func_perror_works="guessing yes" ;;
-                       # Otherwise guess no.
-              *)       gl_cv_func_perror_works="guessing no" ;;
+                       # Otherwise obey --enable-cross-guesses.
+              *)       gl_cv_func_perror_works="$gl_cross_guess_normal" ;;
             esac
            ])
         ])
diff --git a/m4/printf.m4 b/m4/printf.m4
index 6d2280ef5c..d59db20dc3 100644
--- a/m4/printf.m4
+++ b/m4/printf.m4
@@ -1,4 +1,4 @@
-# printf.m4 serial 61
+# printf.m4 serial 62
 dnl Copyright (C) 2003, 2007-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -93,8 +93,8 @@ changequote([,])dnl
                                    [gl_cv_func_printf_sizes_c99="guessing yes"],
                                    [gl_cv_func_printf_sizes_c99="guessing no"])
                                  ;;
-                                 # If we don't know, assume the worst.
-           *)                    gl_cv_func_printf_sizes_c99="guessing no";;
+                                 # If we don't know, obey --enable-cross-guesses.
+           *)                    gl_cv_func_printf_sizes_c99="$gl_cross_guess_normal";;
          esac
         ])
     ])
@@ -271,8 +271,8 @@ changequote([,])dnl
                                    [gl_cv_func_printf_infinite="guessing yes"],
                                    [gl_cv_func_printf_infinite="guessing no"])
                                  ;;
-                                 # If we don't know, assume the worst.
-           *)                    gl_cv_func_printf_infinite="guessing no";;
+                                 # If we don't know, obey --enable-cross-guesses.
+           *)                    gl_cv_func_printf_infinite="$gl_cross_guess_normal";;
          esac
         ])
     ])
@@ -481,8 +481,8 @@ changequote([,])dnl
                                            [gl_cv_func_printf_infinite_long_double="guessing yes"],
                                            [gl_cv_func_printf_infinite_long_double="guessing no"])
                                          ;;
-                                         # If we don't know, assume the worst.
-                   *)                    gl_cv_func_printf_infinite_long_double="guessing no";;
+                                         # If we don't know, obey --enable-cross-guesses.
+                   *)                    gl_cv_func_printf_infinite_long_double="$gl_cross_guess_normal";;
                  esac
                  ;;
              esac
@@ -587,8 +587,8 @@ int main ()
            linux*-android*)      gl_cv_func_printf_directive_a="guessing no";;
                                  # Guess no on native Windows.
            mingw*)               gl_cv_func_printf_directive_a="guessing no";;
-                                 # If we don't know, assume the worst.
-           *)                    gl_cv_func_printf_directive_a="guessing no";;
+                                 # If we don't know, obey --enable-cross-guesses.
+           *)                    gl_cv_func_printf_directive_a="$gl_cross_guess_normal";;
          esac
         ])
     ])
@@ -656,8 +656,8 @@ changequote([,])dnl
                                    [gl_cv_func_printf_directive_f="guessing yes"],
                                    [gl_cv_func_printf_directive_f="guessing no"])
                                  ;;
-                                 # If we don't know, assume the worst.
-           *)                    gl_cv_func_printf_directive_f="guessing no";;
+                                 # If we don't know, obey --enable-cross-guesses.
+           *)                    gl_cv_func_printf_directive_f="$gl_cross_guess_normal";;
          esac
         ])
     ])
@@ -978,8 +978,8 @@ changequote(,)dnl
            linux*-android*) gl_cv_func_printf_flag_zero="guessing no";;
                             # Guess no on native Windows.
            mingw*)          gl_cv_func_printf_flag_zero="guessing no";;
-                            # If we don't know, assume the worst.
-           *)               gl_cv_func_printf_flag_zero="guessing no";;
+                            # If we don't know, obey --enable-cross-guesses.
+           *)               gl_cv_func_printf_flag_zero="$gl_cross_guess_normal";;
          esac
 changequote([,])dnl
         ])
@@ -1156,8 +1156,8 @@ changequote(,)dnl
           haiku*)          gl_cv_func_printf_enomem="guessing yes";;
                            # Guess no on Android.
           linux*-android*) gl_cv_func_printf_enomem="guessing no";;
-                           # If we don't know, assume the worst.
-          *)               gl_cv_func_printf_enomem="guessing no";;
+                           # If we don't know, obey --enable-cross-guesses.
+          *)               gl_cv_func_printf_enomem="$gl_cross_guess_normal";;
         esac
 changequote([,])dnl
       fi
@@ -1255,8 +1255,8 @@ changequote(,)dnl
            linux*-android*)      gl_cv_func_snprintf_truncation_c99="guessing yes";;
                                  # Guess no on native Windows.
            mingw*)               gl_cv_func_snprintf_truncation_c99="guessing no";;
-                                 # If we don't know, assume the worst.
-           *)                    gl_cv_func_snprintf_truncation_c99="guessing no";;
+                                 # If we don't know, obey --enable-cross-guesses.
+           *)                    gl_cv_func_snprintf_truncation_c99="$gl_cross_guess_normal";;
          esac
 changequote([,])dnl
         ])
@@ -1358,8 +1358,8 @@ changequote([,])dnl
                                    [gl_cv_func_snprintf_retval_c99="guessing yes"],
                                    [gl_cv_func_snprintf_retval_c99="guessing no"])
                                  ;;
-                                 # If we don't know, assume the worst.
-           *)                    gl_cv_func_snprintf_retval_c99="guessing no";;
+                                 # If we don't know, obey --enable-cross-guesses.
+           *)                    gl_cv_func_snprintf_retval_c99="$gl_cross_guess_normal";;
          esac
         ])
     ])
@@ -1446,8 +1446,8 @@ changequote(,)dnl
            linux*-android*)      gl_cv_func_snprintf_directive_n="guessing no";;
                                  # Guess no on native Windows.
            mingw*)               gl_cv_func_snprintf_directive_n="guessing no";;
-                                 # If we don't know, assume the worst.
-           *)                    gl_cv_func_snprintf_directive_n="guessing no";;
+                                 # If we don't know, obey --enable-cross-guesses.
+           *)                    gl_cv_func_snprintf_directive_n="$gl_cross_guess_normal";;
          esac
 changequote([,])dnl
         ])
@@ -1601,8 +1601,8 @@ changequote(,)dnl
            linux*-android*)      gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
                                  # Guess yes on native Windows.
            mingw* | pw*)         gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
-                                 # If we don't know, assume the worst.
-           *)                    gl_cv_func_vsnprintf_zerosize_c99="guessing no";;
+                                 # If we don't know, obey --enable-cross-guesses.
+           *)                    gl_cv_func_vsnprintf_zerosize_c99="$gl_cross_guess_normal";;
          esac
 changequote([,])dnl
         ])
diff --git a/m4/pselect.m4 b/m4/pselect.m4
index 5c72b69587..250463d80a 100644
--- a/m4/pselect.m4
+++ b/m4/pselect.m4
@@ -1,4 +1,4 @@
-# pselect.m4 serial 7
+# pselect.m4 serial 8
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -55,8 +55,8 @@ AC_DEFUN([gl_FUNC_PSELECT],
             linux-* | linux) gl_cv_func_pselect_detects_ebadf="guessing yes" ;;
                              # Guess yes on glibc systems.
             *-gnu* | gnu*)   gl_cv_func_pselect_detects_ebadf="guessing yes" ;;
-                             # If we don't know, assume the worst.
-            *)               gl_cv_func_pselect_detects_ebadf="guessing no" ;;
+                             # If we don't know, obey --enable-cross-guesses.
+            *)               gl_cv_func_pselect_detects_ebadf="$gl_cross_guess_normal" ;;
            esac
           ])
       ])
diff --git a/m4/pthread_rwlock_rdlock.m4 b/m4/pthread_rwlock_rdlock.m4
index 85e8dbae50..cbc2df81d2 100644
--- a/m4/pthread_rwlock_rdlock.m4
+++ b/m4/pthread_rwlock_rdlock.m4
@@ -1,4 +1,4 @@
-# pthread_rwlock_rdlock.m4 serial 3
+# pthread_rwlock_rdlock.m4 serial 4
 dnl Copyright (C) 2017-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -170,8 +170,8 @@ main ()
                            gl_cv_pthread_rwlock_rdlock_prefer_writer="guessing no"
                          fi
                          ;;
-                         # If we don't know, assume the worst.
-          *)             gl_cv_pthread_rwlock_rdlock_prefer_writer="guessing no" ;;
+                         # If we don't know, obey --enable-cross-guesses.
+          *)             gl_cv_pthread_rwlock_rdlock_prefer_writer="$gl_cross_guess_normal" ;;
          esac
        ])
      LIBS="$save_LIBS"
diff --git a/m4/ptsname.m4 b/m4/ptsname.m4
index be027b8c0a..5033d90cfe 100644
--- a/m4/ptsname.m4
+++ b/m4/ptsname.m4
@@ -1,4 +1,4 @@
-# ptsname.m4 serial 6
+# ptsname.m4 serial 7
 dnl Copyright (C) 2010-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -30,8 +30,8 @@ AC_DEFUN([gl_FUNC_PTSNAME],
             *-gnu* | gnu*) gl_cv_func_ptsname_sets_errno="guessing yes" ;;
                            # Guess yes on musl systems.
             *-musl*)       gl_cv_func_ptsname_sets_errno="guessing yes" ;;
-                           # If we don't know, assume the worst.
-            *)             gl_cv_func_ptsname_sets_errno="guessing no" ;;
+                           # If we don't know, obey --enable-cross-guesses.
+            *)             gl_cv_func_ptsname_sets_errno="$gl_cross_guess_normal" ;;
           esac
          ])])
     case $gl_cv_func_ptsname_sets_errno in
diff --git a/m4/putenv.m4 b/m4/putenv.m4
index 342ba2636a..1267b901be 100644
--- a/m4/putenv.m4
+++ b/m4/putenv.m4
@@ -1,4 +1,4 @@
-# putenv.m4 serial 23
+# putenv.m4 serial 24
 dnl Copyright (C) 2002-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -40,8 +40,8 @@ AC_DEFUN([gl_FUNC_PUTENV],
                 *-musl*)       gl_cv_func_svid_putenv="guessing yes" ;;
                                # Guess no on native Windows.
                 mingw*)        gl_cv_func_svid_putenv="guessing no" ;;
-                               # If we don't know, assume the worst.
-                *)             gl_cv_func_svid_putenv="guessing no" ;;
+                               # If we don't know, obey --enable-cross-guesses.
+                *)             gl_cv_func_svid_putenv="$gl_cross_guess_normal" ;;
               esac
              ])
    ])
diff --git a/m4/readlink.m4 b/m4/readlink.m4
index 2d7681576c..7aa6ce0337 100644
--- a/m4/readlink.m4
+++ b/m4/readlink.m4
@@ -1,4 +1,4 @@
-# readlink.m4 serial 14
+# readlink.m4 serial 15
 dnl Copyright (C) 2003, 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -38,8 +38,8 @@ AC_DEFUN([gl_FUNC_READLINK],
             linux-* | linux) gl_cv_func_readlink_works="guessing yes" ;;
                              # Guess yes on glibc systems.
             *-gnu* | gnu*)   gl_cv_func_readlink_works="guessing yes" ;;
-                             # If we don't know, assume the worst.
-            *)               gl_cv_func_readlink_works="guessing no" ;;
+                             # If we don't know, obey --enable-cross-guesses.
+            *)               gl_cv_func_readlink_works="$gl_cross_guess_normal" ;;
           esac
          ])
       rm -f conftest.link conftest.lnk2])
diff --git a/m4/realloc.m4 b/m4/realloc.m4
index 93066e80ce..05e7243248 100644
--- a/m4/realloc.m4
+++ b/m4/realloc.m4
@@ -1,11 +1,9 @@
-# realloc.m4 serial 17
+# realloc.m4 serial 18
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
 
-m4_version_prereq([2.70], [] ,[
-
 # This is adapted with modifications from upstream Autoconf here:
 # https://git.savannah.gnu.org/cgit/autoconf.git/commit/?id=04be2b7a29d65d9a08e64e8e56e594c91749598c
 AC_DEFUN([_AC_FUNC_REALLOC_IF],
@@ -35,8 +33,8 @@ AC_DEFUN([_AC_FUNC_REALLOC_IF],
           *-gnu* | gnu* | *-musl* | freebsd* | netbsd* | openbsd* \
           | hpux* | solaris* | cygwin* | mingw*)
             ac_cv_func_realloc_0_nonnull="guessing yes" ;;
-          # If we don't know, assume the worst.
-          *) ac_cv_func_realloc_0_nonnull="guessing no" ;;
+          # If we don't know, obey --enable-cross-guesses.
+          *) ac_cv_func_realloc_0_nonnull="$gl_cross_guess_normal" ;;
         esac
        ])
     ])
@@ -50,8 +48,6 @@ AC_DEFUN([_AC_FUNC_REALLOC_IF],
   esac
 ])# AC_FUNC_REALLOC
 
-])
-
 # gl_FUNC_REALLOC_GNU
 # -------------------
 # Test whether 'realloc (0, 0)' is handled like in GNU libc, and replace
diff --git a/m4/regex.m4 b/m4/regex.m4
index 35119c5c85..ad36dc2b02 100644
--- a/m4/regex.m4
+++ b/m4/regex.m4
@@ -1,4 +1,4 @@
-# serial 68
+# serial 69
 
 # Copyright (C) 1996-2001, 2003-2019 Free Software Foundation, Inc.
 #
@@ -243,8 +243,8 @@ AC_DEFUN([gl_REGEX],
         [case "$host_os" in
                    # Guess no on native Windows.
            mingw*) gl_cv_func_re_compile_pattern_working="guessing no" ;;
-                   # Otherwise, assume it is not working.
-           *)      gl_cv_func_re_compile_pattern_working="guessing no" ;;
+                   # Otherwise obey --enable-cross-guesses.
+           *)      gl_cv_func_re_compile_pattern_working="$gl_cross_guess_normal" ;;
          esac
         ])
       ])
diff --git a/m4/remainder.m4 b/m4/remainder.m4
index e9253a18df..eed78ebf31 100644
--- a/m4/remainder.m4
+++ b/m4/remainder.m4
@@ -1,4 +1,4 @@
-# remainder.m4 serial 8
+# remainder.m4 serial 9
 dnl Copyright (C) 2012-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -98,8 +98,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_remainder_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_remainder_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_remainder_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_remainder_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/remainderf.m4 b/m4/remainderf.m4
index 4c7319a1d8..73287c27fb 100644
--- a/m4/remainderf.m4
+++ b/m4/remainderf.m4
@@ -1,4 +1,4 @@
-# remainderf.m4 serial 12
+# remainderf.m4 serial 13
 dnl Copyright (C) 2012-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -101,8 +101,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_remainderf_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_remainderf_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_remainderf_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_remainderf_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/remainderl.m4 b/m4/remainderl.m4
index dde2f4fca2..b54b5e324b 100644
--- a/m4/remainderl.m4
+++ b/m4/remainderl.m4
@@ -1,4 +1,4 @@
-# remainderl.m4 serial 11
+# remainderl.m4 serial 12
 dnl Copyright (C) 2012-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -106,8 +106,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_remainderl_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_remainderl_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_remainderl_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_remainderl_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/rename.m4 b/m4/rename.m4
index 7318e75771..b453666c6e 100644
--- a/m4/rename.m4
+++ b/m4/rename.m4
@@ -1,4 +1,4 @@
-# serial 31
+# serial 32
 
 # Copyright (C) 2001, 2003, 2005-2006, 2009-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -61,8 +61,8 @@ AC_DEFUN([gl_FUNC_RENAME],
          *-gnu*)          gl_cv_func_rename_slash_dst_works="guessing yes" ;;
                           # Guess no on native Windows.
          mingw*)          gl_cv_func_rename_slash_dst_works="guessing no" ;;
-                          # If we don't know, assume the worst.
-         *)               gl_cv_func_rename_slash_dst_works="guessing no" ;;
+                          # If we don't know, obey --enable-cross-guesses.
+         *)               gl_cv_func_rename_slash_dst_works="$gl_cross_guess_normal" ;;
        esac
       ])
     rm -rf conftest.f conftest.f1 conftest.f2 conftest.d1 conftest.d2 conftest.lnk
@@ -117,8 +117,8 @@ AC_DEFUN([gl_FUNC_RENAME],
          *-gnu*)          gl_cv_func_rename_slash_src_works="guessing yes" ;;
                           # Guess yes on native Windows.
          mingw*)          gl_cv_func_rename_slash_src_works="guessing yes" ;;
-                          # If we don't know, assume the worst.
-         *)               gl_cv_func_rename_slash_src_works="guessing no" ;;
+                          # If we don't know, obey --enable-cross-guesses.
+         *)               gl_cv_func_rename_slash_src_works="$gl_cross_guess_normal" ;;
        esac
       ])
     rm -rf conftest.f conftest.f1 conftest.d1 conftest.d2 conftest.d3 conftest.lnk
@@ -140,53 +140,58 @@ AC_DEFUN([gl_FUNC_RENAME],
   AC_CACHE_CHECK([whether rename manages hard links correctly],
     [gl_cv_func_rename_link_works],
     [if test $ac_cv_func_link = yes; then
-       rm -rf conftest.f conftest.f1 conftest.f2
-       if touch conftest.f conftest.f2 && ln conftest.f conftest.f1 &&
-           set x `ls -i conftest.f conftest.f1` && test "$2" = "$4"; then
-         AC_RUN_IFELSE(
-           [AC_LANG_PROGRAM([[
-#             include <errno.h>
-#             include <stdio.h>
-#             include <stdlib.h>
-#             include <unistd.h>
-              ]],
-              [[int result = 0;
-                if (rename ("conftest.f", "conftest.f1"))
-                  result |= 1;
-                if (unlink ("conftest.f1"))
-                  result |= 2;
+       if test $cross_compiling != yes; then
+         rm -rf conftest.f conftest.f1 conftest.f2
+         if touch conftest.f conftest.f2 && ln conftest.f conftest.f1 &&
+             set x `ls -i conftest.f conftest.f1` && test "$2" = "$4"; then
+           AC_RUN_IFELSE(
+             [AC_LANG_PROGRAM([[
+#               include <errno.h>
+#               include <stdio.h>
+#               include <stdlib.h>
+#               include <unistd.h>
+                ]],
+                [[int result = 0;
+                  if (rename ("conftest.f", "conftest.f1"))
+                    result |= 1;
+                  if (unlink ("conftest.f1"))
+                    result |= 2;
 
-                /* Allow either the POSIX-required behavior, where the
-                   previous rename kept conftest.f, or the (better) NetBSD
-                   behavior, where it removed conftest.f.  */
-                if (rename ("conftest.f", "conftest.f") != 0
-                    && errno != ENOENT)
-                  result |= 4;
+                  /* Allow either the POSIX-required behavior, where the
+                     previous rename kept conftest.f, or the (better) NetBSD
+                     behavior, where it removed conftest.f.  */
+                  if (rename ("conftest.f", "conftest.f") != 0
+                      && errno != ENOENT)
+                    result |= 4;
 
-                if (rename ("conftest.f1", "conftest.f1") == 0)
-                  result |= 8;
-                if (rename ("conftest.f2", "conftest.f2") != 0)
-                  result |= 16;
-                return result;
-              ]])],
-           [gl_cv_func_rename_link_works=yes],
-           [gl_cv_func_rename_link_works=no],
-           dnl When crosscompiling, assume rename is broken.
-           [case "$host_os" in
-                               # Guess yes on Linux systems.
-              linux-* | linux) gl_cv_func_rename_link_works="guessing yes" ;;
-                               # Guess yes on glibc systems.
-              *-gnu*)          gl_cv_func_rename_link_works="guessing yes" ;;
-                               # Guess yes on native Windows.
-              mingw*)          gl_cv_func_rename_link_works="guessing yes" ;;
-                               # If we don't know, assume the worst.
-              *)               gl_cv_func_rename_link_works="guessing no" ;;
-            esac
-           ])
+                  if (rename ("conftest.f1", "conftest.f1") == 0)
+                    result |= 8;
+                  if (rename ("conftest.f2", "conftest.f2") != 0)
+                    result |= 16;
+                  return result;
+                ]])],
+             [gl_cv_func_rename_link_works=yes],
+             [gl_cv_func_rename_link_works=no],
+             [dnl We don't get here.
+              :
+             ])
+         else
+           gl_cv_func_rename_link_works="guessing no"
+         fi
+         rm -rf conftest.f conftest.f1 conftest.f2
        else
-         gl_cv_func_rename_link_works="guessing no"
+         dnl When crosscompiling, assume rename is broken.
+         case "$host_os" in
+                            # Guess yes on Linux systems.
+           linux-* | linux) gl_cv_func_rename_link_works="guessing yes" ;;
+                            # Guess yes on glibc systems.
+           *-gnu*)          gl_cv_func_rename_link_works="guessing yes" ;;
+                            # Guess yes on native Windows.
+           mingw*)          gl_cv_func_rename_link_works="guessing yes" ;;
+                            # If we don't know, obey --enable-cross-guesses.
+           *)               gl_cv_func_rename_link_works="$gl_cross_guess_normal" ;;
+         esac
        fi
-       rm -rf conftest.f conftest.f1 conftest.f2
      else
        gl_cv_func_rename_link_works=yes
      fi
@@ -232,8 +237,8 @@ AC_DEFUN([gl_FUNC_RENAME],
          *-gnu*)          gl_cv_func_rename_dest_works="guessing yes" ;;
                           # Guess no on native Windows.
          mingw*)          gl_cv_func_rename_dest_works="guessing no" ;;
-                          # If we don't know, assume the worst.
-         *)               gl_cv_func_rename_dest_works="guessing no" ;;
+                          # If we don't know, obey --enable-cross-guesses.
+         *)               gl_cv_func_rename_dest_works="$gl_cross_guess_normal" ;;
        esac
       ])
     rm -rf conftest.f conftest.d1 conftest.d2
diff --git a/m4/rintl.m4 b/m4/rintl.m4
index d7e2e90bbb..4e9383f586 100644
--- a/m4/rintl.m4
+++ b/m4/rintl.m4
@@ -1,4 +1,4 @@
-# rintl.m4 serial 6
+# rintl.m4 serial 7
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -56,8 +56,8 @@ int main (int argc, char *argv[])
                *-musl*)       gl_cv_func_rintl_works="guessing yes" ;;
                               # Guess yes on native Windows.
                mingw*)        gl_cv_func_rintl_works="guessing yes" ;;
-                              # If we don't know, assume the worst.
-               *)             gl_cv_func_rintl_works="guessing no" ;;
+                              # If we don't know, obey --enable-cross-guesses.
+               *)             gl_cv_func_rintl_works="$gl_cross_guess_normal" ;;
              esac
             ])
           LIBS="$save_LIBS"
diff --git a/m4/rmdir.m4 b/m4/rmdir.m4
index 5d32caaa4b..bc01778727 100644
--- a/m4/rmdir.m4
+++ b/m4/rmdir.m4
@@ -1,4 +1,4 @@
-# rmdir.m4 serial 16
+# rmdir.m4 serial 17
 dnl Copyright (C) 2002, 2005, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -39,8 +39,8 @@ AC_DEFUN([gl_FUNC_RMDIR],
           *-gnu* | gnu*)   gl_cv_func_rmdir_works="guessing yes" ;;
                            # Guess no on native Windows.
           mingw*)          gl_cv_func_rmdir_works="guessing no" ;;
-                           # If we don't know, assume the worst.
-          *)               gl_cv_func_rmdir_works="guessing no" ;;
+                           # If we don't know, obey --enable-cross-guesses.
+          *)               gl_cv_func_rmdir_works="$gl_cross_guess_normal" ;;
         esac
        ])
      rm -rf conftest.dir conftest.file])
diff --git a/m4/round.m4 b/m4/round.m4
index e4df615724..983fb6851e 100644
--- a/m4/round.m4
+++ b/m4/round.m4
@@ -1,4 +1,4 @@
-# round.m4 serial 21
+# round.m4 serial 22
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -126,8 +126,8 @@ int main (int argc, char *argv[])
                                   [gl_cv_func_round_ieee="guessing yes"],
                                   [gl_cv_func_round_ieee="guessing no"])
                                 ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_round_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_round_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/roundf.m4 b/m4/roundf.m4
index 17cc9da096..7ec988cbdb 100644
--- a/m4/roundf.m4
+++ b/m4/roundf.m4
@@ -1,4 +1,4 @@
-# roundf.m4 serial 22
+# roundf.m4 serial 23
 dnl Copyright (C) 2007-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -126,8 +126,8 @@ int main (int argc, char *argv[])
                                   [gl_cv_func_roundf_ieee="guessing yes"],
                                   [gl_cv_func_roundf_ieee="guessing no"])
                                 ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_roundf_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_roundf_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/roundl.m4 b/m4/roundl.m4
index 934e809527..98a081f32d 100644
--- a/m4/roundl.m4
+++ b/m4/roundl.m4
@@ -1,4 +1,4 @@
-# roundl.m4 serial 19
+# roundl.m4 serial 20
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -70,8 +70,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_roundl_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_roundl_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_roundl_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_roundl_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/select.m4 b/m4/select.m4
index 531c817a18..0805b07819 100644
--- a/m4/select.m4
+++ b/m4/select.m4
@@ -1,4 +1,4 @@
-# select.m4 serial 10
+# select.m4 serial 11
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -78,8 +78,8 @@ changequote([,])dnl
             linux-* | linux) gl_cv_func_select_detects_ebadf="guessing yes" ;;
                              # Guess yes on glibc systems.
             *-gnu* | gnu*)   gl_cv_func_select_detects_ebadf="guessing yes" ;;
-                             # If we don't know, assume the worst.
-            *)               gl_cv_func_select_detects_ebadf="guessing no" ;;
+                             # If we don't know, obey --enable-cross-guesses.
+            *)               gl_cv_func_select_detects_ebadf="$gl_cross_guess_normal" ;;
            esac
           ])
       ])
diff --git a/m4/setenv.m4 b/m4/setenv.m4
index a8f83d60ff..67554596cd 100644
--- a/m4/setenv.m4
+++ b/m4/setenv.m4
@@ -1,4 +1,4 @@
-# setenv.m4 serial 28
+# setenv.m4 serial 29
 dnl Copyright (C) 2001-2004, 2006-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -39,8 +39,8 @@ AC_DEFUN([gl_FUNC_SETENV],
          *-gnu* | gnu*) gl_cv_func_setenv_works="guessing yes" ;;
                         # Guess yes on musl systems.
          *-musl*)       gl_cv_func_setenv_works="guessing yes" ;;
-                        # If we don't know, assume the worst.
-         *)             gl_cv_func_setenv_works="guessing no" ;;
+                        # If we don't know, obey --enable-cross-guesses.
+         *)             gl_cv_func_setenv_works="$gl_cross_guess_normal" ;;
        esac
       ])])
     case "$gl_cv_func_setenv_works" in
@@ -131,8 +131,8 @@ int unsetenv (const char *name);
       [case "$host_os" in
                  # Guess yes on glibc systems.
          *-gnu*) gl_cv_func_unsetenv_works="guessing yes" ;;
-                 # If we don't know, assume the worst.
-         *)      gl_cv_func_unsetenv_works="guessing no" ;;
+                 # If we don't know, obey --enable-cross-guesses.
+         *)      gl_cv_func_unsetenv_works="$gl_cross_guess_normal" ;;
        esac
       ])])
     case "$gl_cv_func_unsetenv_works" in
diff --git a/m4/signbit.m4 b/m4/signbit.m4
index f7f2f3d7af..097682b26a 100644
--- a/m4/signbit.m4
+++ b/m4/signbit.m4
@@ -1,4 +1,4 @@
-# signbit.m4 serial 17
+# signbit.m4 serial 18
 dnl Copyright (C) 2007-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -35,8 +35,8 @@ AC_DEFUN([gl_SIGNBIT],
            *-musl*)       gl_cv_func_signbit="guessing yes" ;;
                           # Guess yes on native Windows.
            mingw*)        gl_cv_func_signbit="guessing yes" ;;
-                          # If we don't know, assume the worst.
-           *)             gl_cv_func_signbit="guessing no" ;;
+                          # If we don't know, obey --enable-cross-guesses.
+           *)             gl_cv_func_signbit="$gl_cross_guess_normal" ;;
          esac
         ])
     ])
@@ -73,8 +73,8 @@ AC_DEFUN([gl_SIGNBIT],
                             gl_cv_func_signbit_gcc="guessing no"
                           fi
                           ;;
-                          # If we don't know, assume the worst.
-           *)             gl_cv_func_signbit_gcc="guessing no" ;;
+                          # If we don't know, obey --enable-cross-guesses.
+           *)             gl_cv_func_signbit_gcc="$gl_cross_guess_normal" ;;
          esac
         ])
     ])
diff --git a/m4/sleep.m4 b/m4/sleep.m4
index 7bab4670a4..397fbd86ee 100644
--- a/m4/sleep.m4
+++ b/m4/sleep.m4
@@ -1,4 +1,4 @@
-# sleep.m4 serial 10
+# sleep.m4 serial 11
 dnl Copyright (C) 2007-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -52,8 +52,8 @@ handle_alarm (int sig)
          *-musl*)       gl_cv_func_sleep_works="guessing yes" ;;
                         # Guess no on native Windows.
          mingw*)        gl_cv_func_sleep_works="guessing no" ;;
-                        # If we don't know, assume the worst.
-         *)             gl_cv_func_sleep_works="guessing no" ;;
+                        # If we don't know, obey --enable-cross-guesses.
+         *)             gl_cv_func_sleep_works="$gl_cross_guess_normal" ;;
        esac
       ])])
     case "$gl_cv_func_sleep_works" in
diff --git a/m4/stat.m4 b/m4/stat.m4
index 60040d1375..752661f8a9 100644
--- a/m4/stat.m4
+++ b/m4/stat.m4
@@ -1,4 +1,4 @@
-# serial 15
+# serial 16
 
 # Copyright (C) 2009-2019 Free Software Foundation, Inc.
 #
@@ -47,8 +47,8 @@ AC_DEFUN([gl_FUNC_STAT],
               linux-* | linux) gl_cv_func_stat_file_slash="guessing yes" ;;
                                # Guess yes on glibc systems.
               *-gnu* | gnu*)   gl_cv_func_stat_file_slash="guessing yes" ;;
-                               # If we don't know, assume the worst.
-              *)               gl_cv_func_stat_file_slash="guessing no" ;;
+                               # If we don't know, obey --enable-cross-guesses.
+              *)               gl_cv_func_stat_file_slash="$gl_cross_guess_normal" ;;
             esac
            ])
          rm -f conftest.tmp conftest.lnk])
diff --git a/m4/stpncpy.m4 b/m4/stpncpy.m4
index f8e1a7c945..e31898fb70 100644
--- a/m4/stpncpy.m4
+++ b/m4/stpncpy.m4
@@ -1,4 +1,4 @@
-# stpncpy.m4 serial 17
+# stpncpy.m4 serial 18
 dnl Copyright (C) 2002-2003, 2005-2007, 2009-2019 Free Software Foundation,
 dnl Inc.
 dnl This file is free software; the Free Software Foundation
@@ -80,7 +80,7 @@ int main ()
 ],         [gl_cv_func_stpncpy="guessing yes"],
            [case "$host_os" in
               *-musl*) gl_cv_func_stpncpy="guessing yes" ;;
-              *)       gl_cv_func_stpncpy="guessing no" ;;
+              *)       gl_cv_func_stpncpy="$gl_cross_guess_normal" ;;
             esac
            ])
         ])
diff --git a/m4/strcasestr.m4 b/m4/strcasestr.m4
index 45abdbd255..97fc5a6a69 100644
--- a/m4/strcasestr.m4
+++ b/m4/strcasestr.m4
@@ -1,4 +1,4 @@
-# strcasestr.m4 serial 24
+# strcasestr.m4 serial 25
 dnl Copyright (C) 2005, 2007-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -64,7 +64,7 @@ AC_DEFUN([gl_FUNC_STRCASESTR_SIMPLE],
 #endif
               ],
               [gl_cv_func_strcasestr_works_always="guessing yes"],
-              [gl_cv_func_strcasestr_works_always="guessing no"])
+              [gl_cv_func_strcasestr_works_always="$gl_cross_guess_normal"])
            ])
         ])
       case "$gl_cv_func_strcasestr_works_always" in
@@ -136,7 +136,7 @@ static void quit (int sig) { _exit (sig + 128); }
 #endif
            ],
            [gl_cv_func_strcasestr_linear="guessing yes"],
-           [gl_cv_func_strcasestr_linear="guessing no"])
+           [gl_cv_func_strcasestr_linear="$gl_cross_guess_normal"])
         ])
       ])
     case "$gl_cv_func_strcasestr_linear" in
diff --git a/m4/strerror.m4 b/m4/strerror.m4
index 2c90f3163c..fbfb4e1753 100644
--- a/m4/strerror.m4
+++ b/m4/strerror.m4
@@ -1,4 +1,4 @@
-# strerror.m4 serial 20
+# strerror.m4 serial 21
 dnl Copyright (C) 2002, 2007-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -28,8 +28,8 @@ AC_DEFUN([gl_FUNC_STRERROR],
            *-gnu* | gnu*) gl_cv_func_working_strerror="guessing yes" ;;
                           # Guess yes on musl systems.
            *-musl*)       gl_cv_func_working_strerror="guessing yes" ;;
-                          # If we don't know, assume the worst.
-           *)             gl_cv_func_working_strerror="guessing no" ;;
+                          # If we don't know, obey --enable-cross-guesses.
+           *)             gl_cv_func_working_strerror="$gl_cross_guess_normal" ;;
          esac
         ])
     ])
@@ -86,8 +86,8 @@ AC_DEFUN([gl_FUNC_STRERROR_0],
          *-musl*)       gl_cv_func_strerror_0_works="guessing yes" ;;
                         # Guess yes on native Windows.
          mingw*)        gl_cv_func_strerror_0_works="guessing yes" ;;
-                        # If we don't know, assume the worst.
-         *)             gl_cv_func_strerror_0_works="guessing no" ;;
+                        # If we don't know, obey --enable-cross-guesses.
+         *)             gl_cv_func_strerror_0_works="$gl_cross_guess_normal" ;;
        esac
       ])
   ])
diff --git a/m4/strerror_r.m4 b/m4/strerror_r.m4
index dafc46d249..9907113e78 100644
--- a/m4/strerror_r.m4
+++ b/m4/strerror_r.m4
@@ -1,4 +1,4 @@
-# strerror_r.m4 serial 19
+# strerror_r.m4 serial 20
 dnl Copyright (C) 2002, 2007-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -163,7 +163,7 @@ changequote([,])dnl
                [gl_cv_func_strerror_r_works=no],
                [dnl Guess no on all platforms that have __xpg_strerror_r,
                 dnl at least until fixed glibc and cygwin are more common.
-                gl_cv_func_strerror_r_works="guessing no"
+                gl_cv_func_strerror_r_works="$gl_cross_guess_normal"
                ])
             ])
         fi
diff --git a/m4/strstr.m4 b/m4/strstr.m4
index d6ed6b993b..23635143c1 100644
--- a/m4/strstr.m4
+++ b/m4/strstr.m4
@@ -1,4 +1,4 @@
-# strstr.m4 serial 20
+# strstr.m4 serial 21
 dnl Copyright (C) 2008-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -56,7 +56,7 @@ AC_DEFUN([gl_FUNC_STRSTR_SIMPLE],
 #endif
             ],
             [gl_cv_func_strstr_works_always="guessing yes"],
-            [gl_cv_func_strstr_works_always="guessing no"])
+            [gl_cv_func_strstr_works_always="$gl_cross_guess_normal"])
          ])
       ])
     case "$gl_cv_func_strstr_works_always" in
@@ -135,7 +135,7 @@ static void quit (int sig) { _exit (sig + 128); }
 #endif
            ],
            [gl_cv_func_strstr_linear="guessing yes"],
-           [gl_cv_func_strstr_linear="guessing no"])
+           [gl_cv_func_strstr_linear="$gl_cross_guess_normal"])
         ])
       ])
     case "$gl_cv_func_strstr_linear" in
diff --git a/m4/strtod.m4 b/m4/strtod.m4
index d68ab7556e..2a0aaea97d 100644
--- a/m4/strtod.m4
+++ b/m4/strtod.m4
@@ -1,4 +1,4 @@
-# strtod.m4 serial 25
+# strtod.m4 serial 26
 dnl Copyright (C) 2002-2003, 2006-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -119,7 +119,7 @@ numeric_equal (double x, double y)
               *-musl*) gl_cv_func_strtod_works="guessing yes" ;;
                        # Guess yes on native Windows.
               mingw*)  gl_cv_func_strtod_works="guessing yes" ;;
-              *)       gl_cv_func_strtod_works="guessing no" ;;
+              *)       gl_cv_func_strtod_works="$gl_cross_guess_normal" ;;
             esac
            ])
         ])
diff --git a/m4/strtold.m4 b/m4/strtold.m4
index 17125fe7b8..389402ac43 100644
--- a/m4/strtold.m4
+++ b/m4/strtold.m4
@@ -1,4 +1,4 @@
-# strtold.m4 serial 4
+# strtold.m4 serial 5
 dnl Copyright (C) 2002-2003, 2006-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -101,7 +101,7 @@ numeric_equal (long double x, long double y)
            [case "$host_os" in
                        # Guess yes on musl systems.
               *-musl*) gl_cv_func_strtold_works="guessing yes" ;;
-              *)       gl_cv_func_strtold_works="guessing no" ;;
+              *)       gl_cv_func_strtold_works="$gl_cross_guess_normal" ;;
             esac
            ])
         ])
diff --git a/m4/symlink.m4 b/m4/symlink.m4
index 508e94dd41..2bec317e9b 100644
--- a/m4/symlink.m4
+++ b/m4/symlink.m4
@@ -1,4 +1,4 @@
-# serial 8
+# serial 9
 # See if we need to provide symlink replacement.
 
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
@@ -40,8 +40,8 @@ AC_DEFUN([gl_FUNC_SYMLINK],
             linux-* | linux) gl_cv_func_symlink_works="guessing yes" ;;
                              # Guess yes on glibc systems.
             *-gnu* | gnu*)   gl_cv_func_symlink_works="guessing yes" ;;
-                             # If we don't know, assume the worst.
-            *)               gl_cv_func_symlink_works="guessing no" ;;
+                             # If we don't know, obey --enable-cross-guesses.
+            *)               gl_cv_func_symlink_works="$gl_cross_guess_normal" ;;
           esac
          ])
       rm -f conftest.f conftest.link conftest.lnk2])
diff --git a/m4/symlinkat.m4 b/m4/symlinkat.m4
index 99ff258068..6b37b51d52 100644
--- a/m4/symlinkat.m4
+++ b/m4/symlinkat.m4
@@ -1,4 +1,4 @@
-# serial 9
+# serial 10
 # See if we need to provide symlinkat replacement.
 
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
@@ -41,8 +41,8 @@ AC_DEFUN([gl_FUNC_SYMLINKAT],
             linux-* | linux) gl_cv_func_symlinkat_works="guessing yes" ;;
                              # Guess yes on glibc systems.
             *-gnu* | gnu*)   gl_cv_func_symlinkat_works="guessing yes" ;;
-                             # If we don't know, assume the worst.
-            *)               gl_cv_func_symlinkat_works="guessing no" ;;
+                             # If we don't know, obey --enable-cross-guesses.
+            *)               gl_cv_func_symlinkat_works="$gl_cross_guess_normal" ;;
           esac
          ])
       rm -f conftest.f conftest.link conftest.lnk2])
diff --git a/m4/trunc.m4 b/m4/trunc.m4
index 9c3694e308..5614148e02 100644
--- a/m4/trunc.m4
+++ b/m4/trunc.m4
@@ -1,4 +1,4 @@
-# trunc.m4 serial 14
+# trunc.m4 serial 15
 dnl Copyright (C) 2007, 2010-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -78,8 +78,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_trunc_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_trunc_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_trunc_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_trunc_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/truncf.m4 b/m4/truncf.m4
index 3ef5b730ed..02dc73d4df 100644
--- a/m4/truncf.m4
+++ b/m4/truncf.m4
@@ -1,4 +1,4 @@
-# truncf.m4 serial 14
+# truncf.m4 serial 15
 dnl Copyright (C) 2007, 2010-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -78,8 +78,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_truncf_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_truncf_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_truncf_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_truncf_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/truncl.m4 b/m4/truncl.m4
index 2970f83437..b0945f6a27 100644
--- a/m4/truncl.m4
+++ b/m4/truncl.m4
@@ -1,4 +1,4 @@
-# truncl.m4 serial 16
+# truncl.m4 serial 17
 dnl Copyright (C) 2007-2008, 2010-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -111,8 +111,8 @@ int main (int argc, char *argv[])
                  *-musl*)       gl_cv_func_truncl_ieee="guessing yes" ;;
                                 # Guess yes on native Windows.
                  mingw*)        gl_cv_func_truncl_ieee="guessing yes" ;;
-                                # If we don't know, assume the worst.
-                 *)             gl_cv_func_truncl_ieee="guessing no" ;;
+                                # If we don't know, obey --enable-cross-guesses.
+                 *)             gl_cv_func_truncl_ieee="$gl_cross_guess_normal" ;;
                esac
               ])
             LIBS="$save_LIBS"
diff --git a/m4/tzset.m4 b/m4/tzset.m4
index afdfa8e675..1e852ac443 100644
--- a/m4/tzset.m4
+++ b/m4/tzset.m4
@@ -1,4 +1,4 @@
-# serial 12
+# serial 13
 
 # Copyright (C) 2003, 2007, 2009-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -74,8 +74,8 @@ main ()
           *-musl*)       gl_cv_func_tzset_clobber="guessing no" ;;
                          # Guess no on native Windows.
           mingw*)        gl_cv_func_tzset_clobber="guessing no" ;;
-                         # If we don't know, assume the worst.
-          *)             gl_cv_func_tzset_clobber="guessing yes" ;;
+                         # If we don't know, obey --enable-cross-guesses.
+          *)             gl_cv_func_tzset_clobber="$gl_cross_guess_inverted" ;;
         esac
        ])
     ])
diff --git a/m4/ungetc.m4 b/m4/ungetc.m4
index 08baf33259..b54c19b95d 100644
--- a/m4/ungetc.m4
+++ b/m4/ungetc.m4
@@ -1,4 +1,4 @@
-# ungetc.m4 serial 7
+# ungetc.m4 serial 8
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -49,8 +49,8 @@ AC_DEFUN_ONCE([gl_FUNC_UNGETC_WORKS],
            *-android*)    gl_cv_func_ungetc_works="guessing yes" ;;
                           # Guess yes on native Windows.
            mingw*)        gl_cv_func_ungetc_works="guessing yes" ;;
-                          # If we don't know, assume the worst.
-           *)             gl_cv_func_ungetc_works="guessing no" ;;
+                          # If we don't know, obey --enable-cross-guesses.
+           *)             gl_cv_func_ungetc_works="$gl_cross_guess_normal" ;;
          esac
         ])
     ])
diff --git a/m4/unlink.m4 b/m4/unlink.m4
index 69fd1af7f8..fec63c1ee8 100644
--- a/m4/unlink.m4
+++ b/m4/unlink.m4
@@ -1,4 +1,4 @@
-# unlink.m4 serial 13
+# unlink.m4 serial 14
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -49,8 +49,8 @@ AC_DEFUN([gl_FUNC_UNLINK],
          *-gnu*)          gl_cv_func_unlink_honors_slashes="guessing yes" ;;
                           # Guess no on native Windows.
          mingw*)          gl_cv_func_unlink_honors_slashes="guessing no" ;;
-                          # If we don't know, assume the worst.
-         *)               gl_cv_func_unlink_honors_slashes="guessing no" ;;
+                          # If we don't know, obey --enable-cross-guesses.
+         *)               gl_cv_func_unlink_honors_slashes="$gl_cross_guess_normal" ;;
        esac
       ])
      rm -f conftest.file conftest.lnk])
@@ -110,8 +110,8 @@ AC_DEFUN([gl_FUNC_UNLINK],
               ]])],
              [gl_cv_func_unlink_parent_fails=yes],
              [gl_cv_func_unlink_parent_fails=no],
-             [# If we don't know, assume the worst.
-              gl_cv_func_unlink_parent_fails="guessing no"
+             [# If we don't know, obey --enable-cross-guesses.
+              gl_cv_func_unlink_parent_fails="$gl_cross_guess_normal"
              ])
            unset GL_SUBDIR_FOR_UNLINK
            rm -rf "$tmp"
diff --git a/m4/usleep.m4 b/m4/usleep.m4
index 4a6bff0bad..4f3abc3df1 100644
--- a/m4/usleep.m4
+++ b/m4/usleep.m4
@@ -1,4 +1,4 @@
-# usleep.m4 serial 6
+# usleep.m4 serial 7
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -35,8 +35,8 @@ AC_DEFUN([gl_FUNC_USLEEP],
            *-musl*)       gl_cv_func_usleep_works="guessing yes" ;;
                           # Guess no on native Windows.
            mingw*)        gl_cv_func_usleep_works="guessing no" ;;
-                          # If we don't know, assume the worst.
-           *)             gl_cv_func_usleep_works="guessing no" ;;
+                          # If we don't know, obey --enable-cross-guesses.
+           *)             gl_cv_func_usleep_works="$gl_cross_guess_normal" ;;
          esac
         ])])
     case "$gl_cv_func_usleep_works" in
diff --git a/m4/utimens.m4 b/m4/utimens.m4
index dda86b09d7..6ed6593406 100644
--- a/m4/utimens.m4
+++ b/m4/utimens.m4
@@ -3,7 +3,7 @@ dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
 
-dnl serial 9
+dnl serial 10
 
 AC_DEFUN([gl_UTIMENS],
 [
@@ -35,8 +35,8 @@ AC_DEFUN([gl_UTIMENS],
            linux-* | linux) gl_cv_func_futimesat_works="guessing yes" ;;
                             # Guess yes on glibc systems.
            *-gnu*)          gl_cv_func_futimesat_works="guessing yes" ;;
-                            # If we don't know, assume the worst.
-           *)               gl_cv_func_futimesat_works="guessing no" ;;
+                            # If we don't know, obey --enable-cross-guesses.
+           *)               gl_cv_func_futimesat_works="$gl_cross_guess_normal" ;;
          esac
         ])
       rm -f conftest.file])
diff --git a/m4/utimes.m4 b/m4/utimes.m4
index 5806d8fbbb..703f823ad5 100644
--- a/m4/utimes.m4
+++ b/m4/utimes.m4
@@ -1,5 +1,5 @@
 # Detect some bugs in glibc's implementation of utimes.
-# serial 6
+# serial 7
 
 dnl Copyright (C) 2003-2005, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
@@ -147,7 +147,7 @@ main ()
           *-musl*) gl_cv_func_working_utimes="guessing yes" ;;
                    # Guess no on native Windows.
           mingw*)  gl_cv_func_working_utimes="guessing no" ;;
-          *)       gl_cv_func_working_utimes="guessing no" ;;
+          *)       gl_cv_func_working_utimes="$gl_cross_guess_normal" ;;
         esac
        ])
     ])
diff --git a/m4/wcwidth.m4 b/m4/wcwidth.m4
index e9b5bf48fc..cb5935a6d7 100644
--- a/m4/wcwidth.m4
+++ b/m4/wcwidth.m4
@@ -1,4 +1,4 @@
-# wcwidth.m4 serial 29
+# wcwidth.m4 serial 30
 dnl Copyright (C) 2006-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -108,7 +108,7 @@ changequote(,)dnl
              *-musl*)       gl_cv_func_wcwidth_works="guessing yes";;
                             # Guess yes on AIX 7 systems.
              aix[7-9]*)     gl_cv_func_wcwidth_works="guessing yes";;
-             *)             gl_cv_func_wcwidth_works="guessing no";;
+             *)             gl_cv_func_wcwidth_works="$gl_cross_guess_normal";;
            esac
 changequote([,])dnl
           ])
author	Bruno Haible <bruno@clisp.org>	2019-09-09 02:43:58 +0200
committer	Bruno Haible <bruno@clisp.org>	2019-09-09 02:43:58 +0200
commit	84cc75b23cedfb03d0339264d46e720650b405e2 (patch)
tree	b3d374339213e790d4497fbb403164dddf641570 /m4
parent	1c58f6921ddfd48b1b39de83999f217e22d62b94 (diff)
download	gnulib-84cc75b23cedfb03d0339264d46e720650b405e2.tar.gz