projects / thirdparty / binutils-gdb.git / blame
| Commit | Line | Data |
|---|---|---|
| dc6c21da TT |
1 | # free.m4 serial 6 |
| 2 | # Copyright (C) 2003-2005, 2009-2022 Free Software Foundation, Inc. | |
| 9c9d63b1 PM |
3 | # This file is free software; the Free Software Foundation |
| 4 | # gives unlimited permission to copy and/or distribute it, | |
| 5 | # with or without modifications, as long as this notice is preserved. | |
| 6 | ||
| 7 | # Written by Paul Eggert and Bruno Haible. | |
| 8 | ||
| 9 | AC_DEFUN([gl_FUNC_FREE], | |
| 10 | [ | |
| 11 | AC_REQUIRE([gl_STDLIB_H_DEFAULTS]) | |
| 12 | ||
| 13 | dnl In the next release of POSIX, free must preserve errno. | |
| 14 | dnl https://www.austingroupbugs.net/view.php?id=385 | |
| 15 | dnl https://sourceware.org/bugzilla/show_bug.cgi?id=17924 | |
| 16 | dnl So far, we know of three platforms that do this: | |
| 17 | dnl * glibc >= 2.33, thanks to the fix for this bug: | |
| 18 | dnl <https://sourceware.org/bugzilla/show_bug.cgi?id=17924> | |
| 19 | dnl * OpenBSD >= 4.5, thanks to this commit: | |
| 20 | dnl <https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdlib/malloc.c.diff?r1=1.100&r2=1.101&f=h> | |
| 21 | dnl * Solaris, because its malloc() implementation is based on brk(), | |
| 22 | dnl not mmap(); hence its free() implementation makes no system calls. | |
| 23 | dnl For other platforms, you can only be sure if they state it in their | |
| 24 | dnl documentation, or by code inspection of the free() implementation in libc. | |
| 25 | AC_CACHE_CHECK([whether free is known to preserve errno], | |
| 26 | [gl_cv_func_free_preserves_errno], | |
| 27 | [AC_COMPILE_IFELSE( | |
| 28 | [AC_LANG_PROGRAM( | |
| 29 | [[#include <stdlib.h> | |
| 30 | ]], | |
| 31 | [[#if 2 < __GLIBC__ + (33 <= __GLIBC_MINOR__) | |
| 32 | #elif defined __OpenBSD__ | |
| 33 | #elif defined __sun | |
| 34 | #else | |
| 35 | #error "'free' is not known to preserve errno" | |
| 36 | #endif | |
| 37 | ]])], | |
| 38 | [gl_cv_func_free_preserves_errno=yes], | |
| 39 | [gl_cv_func_free_preserves_errno=no]) | |
| 40 | ]) | |
| 41 | ||
| 42 | case $gl_cv_func_free_preserves_errno in | |
| dc6c21da TT |
43 | *yes) |
| 44 | AC_DEFINE([HAVE_FREE_POSIX], [1], | |
| 45 | [Define if the 'free' function is guaranteed to preserve errno.]) | |
| 46 | ;; | |
| 9c9d63b1 PM |
47 | *) REPLACE_FREE=1 ;; |
| 48 | esac | |
| 49 | ]) | |
| 50 | ||
| 51 | # Prerequisites of lib/free.c. | |
| 52 | AC_DEFUN([gl_PREREQ_FREE], [:]) |