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Diffstat (limited to 'sntp/m4/ntp_compiler.m4')
| -rw-r--r-- | sntp/m4/ntp_compiler.m4 | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/sntp/m4/ntp_compiler.m4 b/sntp/m4/ntp_compiler.m4 new file mode 100644 index 0000000..2b41866 --- /dev/null +++ b/sntp/m4/ntp_compiler.m4 @@ -0,0 +1,195 @@ +dnl ###################################################################### +dnl Common m4sh code for compiler stuff +AC_DEFUN([NTP_COMPILER], [ +AC_REQUIRE([AC_PROG_CC_C89]) + +CFLAGS_NTP= +CPPFLAGS_NTP= +LDADD_NTP= +LDFLAGS_NTP= +AC_SUBST([CFLAGS_NTP]) +AC_SUBST([CPPFLAGS_NTP]) +AC_SUBST([LDADD_NTP]) +AC_SUBST([LDFLAGS_NTP]) + +case "$ac_cv_prog_cc_c89" in + no) + AC_MSG_WARN([ANSI C89/ISO C90 is the minimum to compile NTP] + [ version 4.2.5 and higher.]) + ;; +esac + +AC_CACHE_CHECK( + [if $CC can handle @%:@warning], + [ntp_cv_cpp_warning], + [AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM([[]], [[#warning foo]])], + [ntp_cv_cpp_warning=yes], + [ntp_cv_cpp_warning=no] + )] +) +case "$ntp_cv_cpp_warning" in + no) + AC_DEFINE([NO_OPTION_NAME_WARNINGS], [1], + [Should we avoid @%:@warning on option name collisions?]) +esac + +AC_CACHE_CHECK( + [if $CC supports __attribute__((...))], + [ntp_cv_cc_attribute], + [AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM( + [[]], + [[void foo(void) __attribute__((__noreturn__));]] + )], + [ntp_cv_cc_attribute=yes], + [ntp_cv_cc_attribute=no] + )] +) +case "$ntp_cv_cc_attribute" in + yes) + AC_DEFINE([HAVE___ATTRIBUTE__], [], + [defined if C compiler supports __attribute__((...))]) +esac +AH_VERBATIM( + [HAVE___ATTRIBUTE___VERBATIM], + [ + /* define away __attribute__() if unsupported */ + #ifndef HAVE___ATTRIBUTE__ + # define __attribute__(x) /* empty */ + #endif + #define ISC_PLATFORM_NORETURN_PRE + #define ISC_PLATFORM_NORETURN_POST __attribute__((__noreturn__)) + ] +) + +case "$GCC" in + yes) + SAVED_CFLAGS="$CFLAGS" + CFLAGS="$CFLAGS -Wstrict-overflow" + AC_CACHE_CHECK( + [if $CC can handle -Wstrict-overflow], + [ntp_cv_gcc_Wstrict_overflow], + [AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM([[]], [[]])], + [ntp_cv_gcc_Wstrict_overflow=yes], + [ntp_cv_gcc_Wstrict_overflow=no] + ) ] + ) + # + # $ntp_cv_gcc_Wstrict_overflow is tested later to add the + # flag to CFLAGS. + # + CFLAGS="$SAVED_CFLAGS -Winit-self" + AC_CACHE_CHECK( + [if $CC can handle -Winit-self], + [ntp_cv_gcc_Winit_self], + [ + AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM([[]], [[]])], + [ntp_cv_gcc_Winit_self=yes], + [ntp_cv_gcc_Winit_self=no] + ) + ] + ) + CFLAGS="$SAVED_CFLAGS" + AS_UNSET([SAVED_CFLAGS]) + # + # $ntp_cv_gcc_Winit_self is tested later to add the + # flag to CFLAGS_NTP. + # + AC_CACHE_CHECK( + [if linker supports omitting unused code and data], + [ntp_cv_gc_sections_runs], + [ + dnl NetBSD will link but likely not run with --gc-sections + dnl http://bugs.ntp.org/1844 + dnl http://gnats.netbsd.org/40401 + dnl --gc-sections causes attempt to load as linux elf, with + dnl wrong syscalls in place. Test a little gauntlet of + dnl simple stdio read code checking for errors, expecting + dnl enough syscall differences that the NetBSD code will + dnl fail even with Linux emulation working as designed. + dnl A shorter test could be refined by someone with access + dnl to a NetBSD host with Linux emulation working. + origCFLAGS="$CFLAGS" + CFLAGS="$CFLAGS -Wl,--gc-sections" + AC_LINK_IFELSE( + [AC_LANG_PROGRAM( + [[ + #include <stdlib.h> + #include <stdio.h> + ]], + [[ + FILE * fpC; + char buf[32]; + size_t cch; + int read_success_once; + + fpC = fopen("conftest.c", "r"); + if (NULL == fpC) + exit(1); + do { + cch = fread(buf, sizeof(buf), 1, fpC); + read_success_once |= (0 != cch); + } while (0 != cch); + if (!read_success_once) + exit(2); + if (!feof(fpC)) + exit(3); + if (0 != fclose(fpC)) + exit(4); + + exit(EXIT_SUCCESS); + ]] + )], + [ + if test "X$cross_compiling" = "Xyes" || grep gc-sections conftest.err ; then + ntp_cv_gc_sections_runs=no + else + ntp_cv_gc_sections_runs=no + ./conftest >/dev/null 2>&1 && ntp_cv_gc_sections_runs=yes + fi + ], + [ntp_cv_gc_sections_runs=no] + ) + CFLAGS="$origCFLAGS" + AS_UNSET([origCFLAGS]) + ] + ) + case "$ntp_cv_gc_sections_runs" in + yes) + LDADD_LIBNTP="-Wl,--gc-sections" + CFLAGS_NTP="$CFLAGS_NTP -ffunction-sections -fdata-sections" + ;; + no) + LDADD_LIBNTP= + ;; + esac + CFLAGS_NTP="$CFLAGS_NTP -Wall" + CFLAGS_NTP="$CFLAGS_NTP -Wcast-align" + CFLAGS_NTP="$CFLAGS_NTP -Wcast-qual" + # CFLAGS_NTP="$CFLAGS_NTP -Wconversion" + # CFLAGS_NTP="$CFLAGS_NTP -Werror" + # CFLAGS_NTP="$CFLAGS_NTP -Wextra" + # CFLAGS_NTP="$CFLAGS_NTP -Wfloat-equal" + CFLAGS_NTP="$CFLAGS_NTP -Wmissing-prototypes" + CFLAGS_NTP="$CFLAGS_NTP -Wpointer-arith" + CFLAGS_NTP="$CFLAGS_NTP -Wshadow" + # CFLAGS_NTP="$CFLAGS_NTP -Wtraditional" + # CFLAGS_NTP="$CFLAGS_NTP -Wwrite-strings" + case "$ntp_cv_gcc_Winit_self" in + yes) + CFLAGS_NTP="$CFLAGS_NTP -Winit-self" + esac + case "$ntp_cv_gcc_Wstrict_overflow" in + yes) + CFLAGS_NTP="$CFLAGS_NTP -Wstrict-overflow" + esac + # -W[no-]strict-prototypes might be added by NTP_OPENSSL +esac + +NTP_OS_CFLAGS + +])dnl +dnl ====================================================================== |