+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.