1 files changed, 59 insertions, 0 deletions
diff --git a/m4/c-strtod.m4 b/m4/c-strtod.m4
new file mode 100644
index 00000000000..d5f5f502cba
--- /dev/null
+++ b/m4/c-strtod.m4
@@ -0,0 +1,59 @@
+# c-strtod.m4 serial 12
+
+# Copyright (C) 2004-2006, 2009-2011 Free Software Foundation, Inc.
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# 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
+])
+
+AC_DEFUN([gl_C_STRTOD],
+[
+  AC_LIBOBJ([c-strtod])
+
+  dnl Prerequisites of lib/c-strtod.c.
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+  AC_CHECK_FUNCS([strtod_l])
+
+  AC_REQUIRE([AC_C_INLINE])
+  :
+])
+
+AC_DEFUN([gl_C_STRTOLD],
+[
+  AC_LIBOBJ([c-strtold])
+
+  dnl Prerequisites of lib/c-strtold.c.
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+  AC_REQUIRE([gl_C99_STRTOLD])
+  AC_CHECK_FUNCS([strtold_l])
+
+  AC_REQUIRE([AC_C_INLINE])
+  :
+])