Back the optimization down from -O3 to -Os. I'm getting an unexplained crasher on -O3. I've looked for a libc++abi bug and can't find one. I'm suspecting clang optimizer bug. But I don't have a good test case at the moment. Deferring investigation on this for now as I will soon be developing more and smaller tests.

llvm-svn: 149414

libcxxabi/lib/buildit

@@ -73,7 +73,7 @@ fi
 set -x
 
 for FILE in ../src/*.cpp; do
-	$CXX -c -g -O3 $RC_CFLAGS $EXTRA_FLAGS -I../include $FILE
+	$CXX -c -g -Os $RC_CFLAGS $EXTRA_FLAGS -I../include $FILE
 done
 case $TRIPLE in
   *-*-mingw*)

libcxxabi/src/cxa_personality.cpp

@@ -774,11 +774,13 @@ _UA_CLEANUP_PHASE
         Transfer control to landing pad.  return _URC_INSTALL_CONTEXT
     
     Else
-    
+
+        This branch handles both normal C++ non-catching handlers (cleanups)
+          and forced unwinding.    
         Scan for anything that can not stop unwinding:
     
             1.  A cleanup.
-        
+
         If a cleanup is found
             transfer control to it. return _URC_INSTALL_CONTEXT
         Else a cleanup is not found: return _URC_CONTINUE_UNWIND