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| author | Bruno Haible <bruno@clisp.org> | 2023-01-27 20:37:19 +0100 |
|---|---|---|
| committer | Bruno Haible <bruno@clisp.org> | 2023-01-27 20:37:19 +0100 |
| commit | c9dfdba295edbd9d2ae8d8ba441d404f357b6c0e (patch) | |
| tree | 68a0334048d63b37fe79e0b7b71600cdc86d1500 /m4 | |
| parent | 267923869ddd11d899a744100eb047fc808b9647 (diff) | |
| download | gnulib-c9dfdba295edbd9d2ae8d8ba441d404f357b6c0e.tar.gz | |
stddef: Fix test-stddef compilation error on FreeBSD 12/x86.
* m4/stddef_h.m4 (gl_STDDEF_H): When testing for good max_align_t, use
an ISO C compliant definition of _Alignof.
Diffstat (limited to 'm4')
| -rw-r--r-- | m4/stddef_h.m4 | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/m4/stddef_h.m4 b/m4/stddef_h.m4 index c0553d6f2f..a2322ebb7e 100644 --- a/m4/stddef_h.m4 +++ b/m4/stddef_h.m4 @@ -1,4 +1,4 @@ -# stddef_h.m4 serial 12 +# stddef_h.m4 serial 13 dnl Copyright (C) 2009-2023 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, @@ -22,7 +22,14 @@ AC_DEFUN_ONCE([gl_STDDEF_H], [gl_cv_type_max_align_t], [AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( - [[#include <stddef.h> + [[/* On FreeBSD 12.0/x86, max_align_t defined by <stddef.h> has + the correct alignment with the default (wrong) definition of + _Alignof, but a wrong alignment as soon as we activate an + ISO C compliant _Alignof definition. */ + #if ((defined __GNUC__ && 4 <= __GNUC__) || defined __clang__) && !defined __cplusplus + #define _Alignof(type) __builtin_offsetof (struct { char __a; type __b; }, __b) + #endif + #include <stddef.h> unsigned int s = sizeof (max_align_t); #if defined __GNUC__ || defined __clang__ || defined __IBM__ALIGNOF__ int check1[2 * (__alignof__ (double) <= __alignof__ (max_align_t)) - 1]; |