Avoid recursion in VG_(exit).



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@10285 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/coregrind/m_libcassert.c b/coregrind/m_libcassert.c
index b6bdbbe..8e3eba2 100644
--- a/coregrind/m_libcassert.c
+++ b/coregrind/m_libcassert.c
@@ -107,7 +107,10 @@
 #  error Unknown OS
 #endif
    /*NOTREACHED*/
-   VG_(core_panic)("VG_(exit) didn't work?");
+   // We really shouldn't reach here.  Just in case we do, use some very crude
+   // methods to force abort
+   __builtin_trap();
+   *(volatile Int*)0 = 'x';
 }
 
 // Print the scheduler status.