c-strtod, c-strtold: Use the bug fixes for strtod, strtold.

* lib/stdlib.in.h (GNULIB_defined_strtod_function,
GNULIB_defined_strtold_function): New macros.
* lib/c-strtod.c (HAVE_GOOD_STRTOD_L): New macro.
(STRTOD): Ignore HAVE_C99_STRTOLD.
(c_locale): Don't define it on platforms where strtod_l/strtold_l is
deemed buggy. But do use it on platforms where uselocale exists and is
usable.
(C_STRTOD): Don't use STRTOD_L on platforms where strtod_l/strtold_l is
deemed buggy. On platforms where uselocale exists and is usable, use
uselocale and strtod/strtold.
* m4/c-strtod.m4 (gl_C99_STRTOLD): Remove macro.
(gl_C_STRTOD): Require gt_FUNC_USELOCALE.
(gl_C_STRTOLD): Likewise. Define HAVE_C99_STRTOLD unconditionally.
* modules/c-strtod (Files): Add m4/intl-thread-locale.m4.
(Depends-on): Add strtod.
* modules/c-strtold (Files): Add m4/intl-thread-locale.m4.
(Depends-on): Add strtold.

1 files changed, 5 insertions, 28 deletions

diff --git a/m4/c-strtod.m4 b/m4/c-strtod.m4
index 1694a2396c..1d4b7f860c 100644
--- a/m4/c-strtod.m4
+++ b/m4/c-strtod.m4
@@ -1,4 +1,4 @@
-# c-strtod.m4 serial 16
+# c-strtod.m4 serial 17
 
 # Copyright (C) 2004-2006, 2009-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -7,36 +7,11 @@
 
 # Written by Paul Eggert.
 
-AC_DEFUN([gl_C99_STRTOLD],
-[
-  AC_CACHE_CHECK([whether strtold conforms to C99],
-    [gl_cv_func_c99_strtold],
-    [AC_LINK_IFELSE(
-       [AC_LANG_PROGRAM(
-          [[/* On HP-UX before 11.23, strtold returns a struct instead of
-                long double.  Reject implementations like that, by requiring
-                compatibility with the C99 prototype.  */
-             #include <stdlib.h>
-             static long double (*p) (char const *, char **) = strtold;
-             static long double
-             test (char const *nptr, char **endptr)
-             {
-               long double r;
-               r = strtold (nptr, endptr);
-               return r;
-             }]],
-           [[return test ("1.0", NULL) != 1 || p ("1.0", NULL) != 1;]])],
-       [gl_cv_func_c99_strtold=yes],
-       [gl_cv_func_c99_strtold=no])])
-  if test $gl_cv_func_c99_strtold = yes; then
-    AC_DEFINE([HAVE_C99_STRTOLD], [1], [Define to 1 if strtold conforms to C99.])
-  fi
-])
-
 dnl Prerequisites of lib/c-strtod.c.
 AC_DEFUN([gl_C_STRTOD],
 [
   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+  AC_REQUIRE([gt_FUNC_USELOCALE])
 
   AC_CHECK_HEADERS_ONCE([xlocale.h])
   dnl We can't use AC_CHECK_FUNC here, because strtod_l() is defined as a
@@ -71,6 +46,8 @@ dnl Prerequisites of lib/c-strtold.c.
 AC_DEFUN([gl_C_STRTOLD],
 [
   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
-  AC_REQUIRE([gl_C99_STRTOLD])
+  AC_REQUIRE([gt_FUNC_USELOCALE])
+  AC_DEFINE([HAVE_C99_STRTOLD], [1],
+    [Define to 1 because the gnulib 'strtold' module provides a C99-conforming strtold function.])
   AC_CHECK_FUNCS([strtold_l])
 ])