From 7955dc93ef02c0cb90a8c4966abf142a3813ff48 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Thu, 4 Mar 2021 00:47:19 -0800 Subject: [PATCH] stdalign: port to tcc + glibc MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit * lib/stdalign.in.h (_Alignas): Do not define using __attribute__ if __attribute__ is defined as a macro, as __attribute__ surely a no-op in that case and this is an area where __attribute__ cannot simply be ignored. * m4/stdalign.m4 (gl_STDALIGN_H): Include so that it #defines __attribute__(x) to nothing on glibc-based systems when non-GNU-C-compatible compilers are used. This exposes a bug in Tiny C Compiler 0.9.27’s implementation of _Alignas on glibc platforms. --- ChangeLog | 13 +++++++++++++ lib/stdalign.in.h | 13 +++++++------ m4/stdalign.m4 | 4 +++- 3 files changed, 23 insertions(+), 7 deletions(-) diff --git a/ChangeLog b/ChangeLog index 9f6818c17..50d247fac 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,16 @@ +2021-03-04 Paul Eggert + + stdalign: port to tcc + glibc + * lib/stdalign.in.h (_Alignas): Do not define using __attribute__ + if __attribute__ is defined as a macro, as __attribute__ surely a + no-op in that case and this is an area where __attribute__ cannot + simply be ignored. + * m4/stdalign.m4 (gl_STDALIGN_H): Include so that + it #defines __attribute__(x) to nothing on glibc-based systems + when non-GNU-C-compatible compilers are used. + This exposes a bug in Tiny C Compiler 0.9.27’s implementation + of _Alignas on glibc platforms. + 2021-03-03 Bruno Haible asyncsafe-spin, simple-atomic: Add support for tcc/x86. diff --git a/lib/stdalign.in.h b/lib/stdalign.in.h index e7a7402ee..52a4a7b6e 100644 --- a/lib/stdalign.in.h +++ b/lib/stdalign.in.h @@ -104,12 +104,13 @@ #if !defined __STDC_VERSION__ || __STDC_VERSION__ < 201112 # if defined __cplusplus && 201103 <= __cplusplus # define _Alignas(a) alignas (a) -# elif ((defined __APPLE__ && defined __MACH__ \ - ? 4 < __GNUC__ + (1 <= __GNUC_MINOR__) \ - : __GNUC__ && !defined __ibmxl__) \ - || (4 <= __clang_major__) \ - || (__ia64 && (61200 <= __HP_cc || 61200 <= __HP_aCC)) \ - || __ICC || 0x590 <= __SUNPRO_C || 0x0600 <= __xlC__) +# elif (!defined __attribute__ \ + && ((defined __APPLE__ && defined __MACH__ \ + ? 4 < __GNUC__ + (1 <= __GNUC_MINOR__) \ + : __GNUC__ && !defined __ibmxl__) \ + || (4 <= __clang_major__) \ + || (__ia64 && (61200 <= __HP_cc || 61200 <= __HP_aCC)) \ + || __ICC || 0x590 <= __SUNPRO_C || 0x0600 <= __xlC__)) # define _Alignas(a) __attribute__ ((__aligned__ (a))) # elif 1300 <= _MSC_VER # define _Alignas(a) __declspec (align (a)) diff --git a/m4/stdalign.m4 b/m4/stdalign.m4 index 8dcb634d5..e22d7f78c 100644 --- a/m4/stdalign.m4 +++ b/m4/stdalign.m4 @@ -13,7 +13,8 @@ AC_DEFUN([gl_STDALIGN_H], [gl_cv_header_working_stdalign_h], [AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( - [[#include + [[#include + #include #include /* Test that alignof yields a result consistent with offsetof. @@ -32,6 +33,7 @@ AC_DEFUN([gl_STDALIGN_H], /* Test _Alignas only on platforms where gnulib can help. */ #if \ ((defined __cplusplus && 201103 <= __cplusplus) \ + || (__TINYC__ && defined __attribute__) \ || (defined __APPLE__ && defined __MACH__ \ ? 4 < __GNUC__ + (1 <= __GNUC_MINOR__) \ : __GNUC__) \ -- 2.27.0