From c947dcc1822d923b76607944d17cd43151165660 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 10 Jun 2010 16:01:32 +0000 Subject: [PATCH] sync changelog with gcc, plus commit the following patch: 2010-06-09 Iain Sandoe PR bootstrap/43170 * tls.m4 (GCC_CHECK_TLS): Add volatile qualifier to the test references. Move the main () test reference ahead of pthread_create(). Add a comment to explain the requirements of the test. --- config/ChangeLog | 28 +++++++++++++++++++--------- config/tls.m4 | 11 ++++++++--- 2 files changed, 27 insertions(+), 12 deletions(-) diff --git a/config/ChangeLog b/config/ChangeLog index e0561d2f1..27f49c2ee 100644 --- a/config/ChangeLog +++ b/config/ChangeLog @@ -1,25 +1,35 @@ +2010-06-09 Iain Sandoe + + PR bootstrap/43170 + * tls.m4 (GCC_CHECK_TLS): Add volatile qualifier to the test + references. Move the main () test reference ahead of + pthread_create(). Add a comment to explain the requirements + of the test. + 2010-06-03 Joern Rennecke - Ralf Wildenhues + Ralf Wildenhues - Sync from GCC: PR bootstrap/42798 * override.m4 (_AC_CHECK_DECL_BODY, _AC_CHECK_DECLS): Import definitions from git Autoconf. -2010-06-01 Ralf Wildenhues - - Sync from GCC: +2010-04-13 Steve Ellcey - 2010-04-13 Steve Ellcey * elf.m4: Add hppa[12]*-*-hpux* to list of non-elf platforms. - 2010-01-05 Rainer Orth +2010-03-23 Kai Tietz + + * mh-mingw: Revert accidentally checking r156315. + +2010-01-05 Rainer Orth + * stdint.m4 (GCC_HEADER_STDINT): Don't typedef uint8_t etc. if corresponding macros already exist. -2010-02-15 Nick Clifton +2010-01-02 Richard Guenther - * elf.m4: Import from gcc mainline. + PR lto/41529 + * elf.m4: New file. 2009-11-30 Joseph Myers diff --git a/config/tls.m4 b/config/tls.m4 index ef7e6d0b5..4e170c8d6 100644 --- a/config/tls.m4 +++ b/config/tls.m4 @@ -38,11 +38,16 @@ AC_DEFUN([GCC_CHECK_TLS], [ CFLAGS="$chktls_save_CFLAGS" if test "X$thread_CFLAGS" != Xfailed; then CFLAGS="$thread_CFLAGS $chktls_save_CFLAGS" + dnl Test for an old glibc bug that violated the __thread property. + dnl Use volatile to ensure the compiler won't optimize away pointer + dnl accesses it might otherwise assume to be redundant, or reorder + dnl them and reuse storage, which might lead to them pointing to + dnl the same location. AC_RUN_IFELSE( [AC_LANG_PROGRAM( [#include __thread int a; - static int *a_in_other_thread; + static int *volatile a_in_other_thread; static void * thread_func (void *arg) { @@ -51,11 +56,11 @@ AC_DEFUN([GCC_CHECK_TLS], [ }], [pthread_t thread; void *thread_retval; - int *a_in_main_thread; + int *volatile a_in_main_thread; + a_in_main_thread = &a; if (pthread_create (&thread, (pthread_attr_t *)0, thread_func, (void *)0)) return 0; - a_in_main_thread = &a; if (pthread_join (thread, &thread_retval)) return 0; return (a_in_other_thread == a_in_main_thread);])], -- 2.43.5