On 18 Oct 2011, at 13:31, Arnaud Charlet wrote:
It's broken in all Libc versions that are in the wild (AFAICT from
looking
at the released sources).
We will need to deal with
configury/__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ stuff once
there is a fixed Libc.
OK, would be good to follow up with such patch when/if this is fixed.
We are waiting for input re. the actual bug (in system code).
In the meantime, I've applied the patch as a (hopefully temporary)
workaround.
cheers
Iain
Index: gcc/ada/ChangeLog
===================================================================
--- gcc/ada/ChangeLog (revision 180612)
+++ gcc/ada/ChangeLog (working copy)
@@ -1,3 +1,11 @@
+2011-10-28 Iain Sandoe <ia...@gcc.gnu.org>
+ Eric Botcazou <ebotca...@adacore.com>
+
+ PR target/50678
+ * init.c (Darwin/__gnat_error_handler): Apply a work-around to the
+ bug [filed as radar #10302855], which is inconsistent unwind data
+ for sigtramp.
+
2011-10-28 Eric Botcazou <ebotca...@adacore.com>
PR ada/50842
Index: gcc/ada/init.c
===================================================================
--- gcc/ada/init.c (revision 180612)
+++ gcc/ada/init.c (working copy)
@@ -2287,6 +2287,16 @@ __gnat_error_handler (int sig, siginfo_t *si, void
{
struct Exception_Data *exception;
const char *msg;
+#if defined (__x86_64__)
+ /* Work around radar #10302855/pr50678, where the unwinders (libunwind or
+ libgcc_s depending on the system revision) and the DWARF unwind data for
+ the sigtramp have different ideas about register numbering (causing rbx
+ and rdx to be transposed).. */
+ ucontext_t *uc = (ucontext_t *)ucontext ;
+ unsigned long t = uc->uc_mcontext->__ss.__rbx;
+ uc->uc_mcontext->__ss.__rbx = uc->uc_mcontext->__ss.__rdx;
+ uc->uc_mcontext->__ss.__rdx = t;
+#endif
switch (sig)
{
