1 # c-strtod.m4 serial 16
3 # Copyright (C) 2004-2006, 2009-2019 Free Software Foundation, Inc.
4 # This file is free software; the Free Software Foundation
5 # gives unlimited permission to copy and/or distribute it,
6 # with or without modifications, as long as this notice is preserved.
8 # Written by Paul Eggert.
10 AC_DEFUN([gl_C99_STRTOLD],
12 AC_CACHE_CHECK([whether strtold conforms to C99],
13 [gl_cv_func_c99_strtold],
16 [[/* On HP-UX before 11.23, strtold returns a struct instead of
17 long double. Reject implementations like that, by requiring
18 compatibility with the C99 prototype. */
20 static long double (*p) (char const *, char **) = strtold;
22 test (char const *nptr, char **endptr)
25 r = strtold (nptr, endptr);
28 [[return test ("1.0", NULL) != 1 || p ("1.0", NULL) != 1;]])],
29 [gl_cv_func_c99_strtold=yes],
30 [gl_cv_func_c99_strtold=no])])
31 if test $gl_cv_func_c99_strtold = yes; then
32 AC_DEFINE([HAVE_C99_STRTOLD], [1], [Define to 1 if strtold conforms to C99.])
36 dnl Prerequisites of lib/c-strtod.c.
37 AC_DEFUN([gl_C_STRTOD],
39 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
41 AC_CHECK_HEADERS_ONCE([xlocale.h])
42 dnl We can't use AC_CHECK_FUNC here, because strtod_l() is defined as a
43 dnl static inline function when compiling for Android 7.1 or older.
44 AC_CACHE_CHECK([for strtod_l], [gl_cv_func_strtod_l],
55 return strtod_l("0",&end,loc) < 0.0;
58 [gl_cv_func_strtod_l=yes],
59 [gl_cv_func_strtod_l=no])
61 if test $gl_cv_func_strtod_l = yes; then
66 AC_DEFINE_UNQUOTED([HAVE_STRTOD_L], [$HAVE_STRTOD_L],
67 [Define to 1 if the system has the 'strtod_l' function.])
70 dnl Prerequisites of lib/c-strtold.c.
71 AC_DEFUN([gl_C_STRTOLD],
73 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
74 AC_REQUIRE([gl_C99_STRTOLD])
75 AC_CHECK_FUNCS([strtold_l])