Branch
Hash :
7b089321
Author :
Date :
2025-01-01T09:24:36
maint: run 'make update-copyright'
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72
# eealloc.m4
# serial 6
dnl Copyright (C) 2003, 2009-2025 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
dnl This file is offered as-is, without any warranty.
AC_DEFUN([gl_EEALLOC],
[
AC_REQUIRE([gl_EEMALLOC])
AC_REQUIRE([gl_EEREALLOC])
])
AC_DEFUN([gl_EEMALLOC],
[
_AC_FUNC_MALLOC_IF(
[gl_cv_func_malloc_0_nonnull=1],
[gl_cv_func_malloc_0_nonnull=0],
["$gl_cross_guess_normal"])
AC_DEFINE_UNQUOTED([MALLOC_0_IS_NONNULL], [$gl_cv_func_malloc_0_nonnull],
[If malloc(0) is != NULL, define this to 1. Otherwise define this
to 0.])
])
AC_DEFUN([gl_EEREALLOC],
[
_AC_FUNC_REALLOC_IF(
[gl_cv_func_realloc_0_nonnull=1],
[gl_cv_func_realloc_0_nonnull=0],
["$gl_cross_guess_normal"])
AC_DEFINE_UNQUOTED([REALLOC_0_IS_NONNULL], [$gl_cv_func_realloc_0_nonnull],
[If realloc(NULL,0) is != NULL, define this to 1. Otherwise define this
to 0.])
])
m4_version_prereq([2.73], [], [
# This is copied from upstream Autoconf here:
# https://git.savannah.gnu.org/cgit/autoconf.git/tree/lib/autoconf/functions.m4?id=1f38316f6af7bf63e5e7dd187ff6456e07ad743e#n1483
# _AC_FUNC_REALLOC_IF(IF-WORKS, IF-NOT[, UNKNOWN-ASSUME])
# -------------------------------------------------------
# If 'realloc (0, 0)' returns nonnull, run IF-WORKS, otherwise, IF-NOT.
# If it is not known whether it works, assume the shell word UNKNOWN-ASSUME,
# which should end in "yes" or in something else (the latter is the default).
AC_DEFUN([_AC_FUNC_REALLOC_IF],
[
AC_REQUIRE([AC_CANONICAL_HOST])dnl for cross-compiles
AC_CACHE_CHECK([whether realloc (0, 0) returns nonnull],
[ac_cv_func_realloc_0_nonnull],
[AC_RUN_IFELSE(
[AC_LANG_PROGRAM(
[[#include <stdlib.h>
/* Use prealloc to test; 'volatile' prevents the compiler
from optimizing the realloc call away. */
void *(*volatile prealloc) (void *, size_t) = realloc;]],
[[void *p = prealloc (0, 0);
int result = !p;
free (p);
return result;]])],
[ac_cv_func_realloc_0_nonnull=yes],
[ac_cv_func_realloc_0_nonnull=no],
[AS_CASE([$host_os],
[# Guess yes on platforms where we know the result.
*-gnu* | freebsd* | netbsd* | openbsd* | bitrig* \
| gnu* | *-musl* | midipix* | midnightbsd* \
| hpux* | solaris* | cygwin* | mingw* | windows* | msys*],
[ac_cv_func_realloc_0_nonnull="guessing yes"],
[# Guess as follows if we don't know.
ac_cv_func_realloc_0_nonnull=m4_default([$3], ["guessing no"])])])])
AS_CASE([$ac_cv_func_realloc_0_nonnull], [*yes], [$1], [$2])
])# _AC_FUNC_REALLOC_IF
])