2012-06-13 Basile Starynkevitch <basile@starynkevitch.net>

	MELT branch merged with trunk rev 188512 using svnmerge



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/melt-branch@188515 138bc75d-0d04-0410-961f-82ee72b054a4

5 files changed, 49 insertions, 8 deletions

diff --git a/libgcc/ChangeLog b/libgcc/ChangeLog
index dd1dc5504a5..9308090e32c 100644
--- a/libgcc/ChangeLog
+++ b/libgcc/ChangeLog
@@ -1,3 +1,15 @@
+2012-06-11  Sriraman Tallam  <tmsriram@google.com>
+
+	* config/i386/libgcc-bsd.ver: Version symbol __cpu_indicator_init.
+	* config/i386/libgcc-sol2.ver: Ditto.
+	* config/i386/libgcc-glibc.ver: Ditto.
+
+2012-06-11  Roland McGrath  <mcgrathr@google.com>
+
+	* gthr-posix.h [neither FreeBSD nor Solaris] (__gthread_active_p):
+	If __GLIBC__ is defined, refer to __pthread_key_create instead of
+	pthread_cancel.
+
 2012-06-09  Uros Bizjak  <ubizjak@gmail.com>
 
 	* config/i386/32/sfp-machine.h (__gcc_CMPtype, CMPtype,
diff --git a/libgcc/config/i386/libgcc-bsd.ver b/libgcc/config/i386/libgcc-bsd.ver
index 74622bf7763..0c4b47496bf 100644
--- a/libgcc/config/i386/libgcc-bsd.ver
+++ b/libgcc/config/i386/libgcc-bsd.ver
@@ -109,4 +109,5 @@ GCC_4.6.0 {
 
 GCC_4.8.0 {
   __cpu_model
+  __cpu_indicator_init
 }
diff --git a/libgcc/config/i386/libgcc-glibc.ver b/libgcc/config/i386/libgcc-glibc.ver
index 07fd1f9c5a7..3bfb0286c29 100644
--- a/libgcc/config/i386/libgcc-glibc.ver
+++ b/libgcc/config/i386/libgcc-glibc.ver
@@ -150,6 +150,7 @@ GCC_4.3.0 {
 
 GCC_4.8.0 {
   __cpu_model
+  __cpu_indicator_init
 }
 %else
 GCC_4.4.0 {
@@ -190,5 +191,6 @@ GCC_4.5.0 {
 
 GCC_4.8.0 {
   __cpu_model
+  __cpu_indicator_init
 }
 %endif
diff --git a/libgcc/config/i386/libgcc-sol2.ver b/libgcc/config/i386/libgcc-sol2.ver
index af8a9a0bddb..0aa0499b869 100644
--- a/libgcc/config/i386/libgcc-sol2.ver
+++ b/libgcc/config/i386/libgcc-sol2.ver
@@ -109,4 +109,5 @@ GCC_4.5.0 {
 
 GCC_4.8.0 {
   __cpu_model
+  __cpu_indicator_init
 }
diff --git a/libgcc/gthr-posix.h b/libgcc/gthr-posix.h
index b5b161184f4..cc4e518f5b9 100644
--- a/libgcc/gthr-posix.h
+++ b/libgcc/gthr-posix.h
@@ -212,18 +212,43 @@ __gthread_active_p (void)
 
 #else /* neither FreeBSD nor Solaris */
 
+/* For a program to be multi-threaded the only thing that it certainly must
+   be using is pthread_create.  However, there may be other libraries that
+   intercept pthread_create with their own definitions to wrap pthreads
+   functionality for some purpose.  In those cases, pthread_create being
+   defined might not necessarily mean that libpthread is actually linked
+   in.
+
+   For the GNU C library, we can use a known internal name.  This is always
+   available in the ABI, but no other library would define it.  That is
+   ideal, since any public pthread function might be intercepted just as
+   pthread_create might be.  __pthread_key_create is an "internal"
+   implementation symbol, but it is part of the public exported ABI.  Also,
+   it's among the symbols that the static libpthread.a always links in
+   whenever pthread_create is used, so there is no danger of a false
+   negative result in any statically-linked, multi-threaded program.
+
+   For others, we choose pthread_cancel as a function that seems unlikely
+   to be redefined by an interceptor library.  The bionic (Android) C
+   library does not provide pthread_cancel, so we do use pthread_create
+   there (and interceptor libraries lose).  */
+
+#ifdef __GLIBC__
+__gthrw2(__gthrw_(__pthread_key_create),
+	 __pthread_key_create,
+	 pthread_key_create)
+# define GTHR_ACTIVE_PROXY	__gthrw_(__pthread_key_create)
+#elif defined (__BIONIC__)
+# define GTHR_ACTIVE_PROXY	__gthrw_(pthread_create)
+#else
+# define GTHR_ACTIVE_PROXY	__gthrw_(pthread_cancel)
+#endif
+
 static inline int
 __gthread_active_p (void)
 {
-/* Android's C library does not provide pthread_cancel, check for
-   `pthread_create' instead.  */
-#ifndef __BIONIC__
   static void *const __gthread_active_ptr
-    = __extension__ (void *) &__gthrw_(pthread_cancel);
-#else
-  static void *const __gthread_active_ptr
-    = __extension__ (void *) &__gthrw_(pthread_create);
-#endif
+    = __extension__ (void *) &GTHR_ACTIVE_PROXY;
   return __gthread_active_ptr != 0;
 }