1# realloc.m4 serial 19 2dnl Copyright (C) 2007, 2009-2021 Free Software Foundation, Inc. 3dnl This file is free software; the Free Software Foundation 4dnl gives unlimited permission to copy and/or distribute it, 5dnl with or without modifications, as long as this notice is preserved. 6 7# This is adapted with modifications from upstream Autoconf here: 8# https://git.savannah.gnu.org/cgit/autoconf.git/commit/?id=04be2b7a29d65d9a08e64e8e56e594c91749598c 9AC_DEFUN([_AC_FUNC_REALLOC_IF], 10[ 11 AC_REQUIRE([AC_CANONICAL_HOST])dnl for cross-compiles 12 AC_CACHE_CHECK([for GNU libc compatible realloc], 13 [ac_cv_func_realloc_0_nonnull], 14 [AC_RUN_IFELSE( 15 [AC_LANG_PROGRAM( 16 [[#include <stdlib.h> 17 ]], 18 [[char *p = realloc (0, 0); 19 int result = !p; 20 free (p); 21 return result;]]) 22 ], 23 [ac_cv_func_realloc_0_nonnull=yes], 24 [ac_cv_func_realloc_0_nonnull=no], 25 [case "$host_os" in 26 # Guess yes on platforms where we know the result. 27 *-gnu* | gnu* | *-musl* | freebsd* | netbsd* | openbsd* \ 28 | hpux* | solaris* | cygwin* | mingw*) 29 ac_cv_func_realloc_0_nonnull="guessing yes" ;; 30 # If we don't know, obey --enable-cross-guesses. 31 *) ac_cv_func_realloc_0_nonnull="$gl_cross_guess_normal" ;; 32 esac 33 ]) 34 ]) 35 case "$ac_cv_func_realloc_0_nonnull" in 36 *yes) 37 $1 38 ;; 39 *) 40 $2 41 ;; 42 esac 43])# AC_FUNC_REALLOC 44 45# gl_FUNC_REALLOC_GNU 46# ------------------- 47# Test whether 'realloc (0, 0)' is handled like in GNU libc, and replace 48# realloc if it is not. 49AC_DEFUN([gl_FUNC_REALLOC_GNU], 50[ 51 AC_REQUIRE([gl_STDLIB_H_DEFAULTS]) 52 dnl _AC_FUNC_REALLOC_IF is defined in Autoconf. 53 _AC_FUNC_REALLOC_IF( 54 [AC_DEFINE([HAVE_REALLOC_GNU], [1], 55 [Define to 1 if your system has a GNU libc compatible 'realloc' 56 function, and to 0 otherwise.])], 57 [AC_DEFINE([HAVE_REALLOC_GNU], [0]) 58 REPLACE_REALLOC=1 59 ]) 60])# gl_FUNC_REALLOC_GNU 61 62# gl_FUNC_REALLOC_POSIX 63# --------------------- 64# Test whether 'realloc' is POSIX compliant (sets errno to ENOMEM when it 65# fails), and replace realloc if it is not. 66AC_DEFUN([gl_FUNC_REALLOC_POSIX], 67[ 68 AC_REQUIRE([gl_STDLIB_H_DEFAULTS]) 69 AC_REQUIRE([gl_CHECK_MALLOC_POSIX]) 70 if test $gl_cv_func_malloc_posix = yes; then 71 AC_DEFINE([HAVE_REALLOC_POSIX], [1], 72 [Define if the 'realloc' function is POSIX compliant.]) 73 else 74 REPLACE_REALLOC=1 75 fi 76]) 77