[committed] Add -mbackchain to deep-stack-uaf-1.C testcase (PR sanitizer/79341)

[Jakub Jelinek]

Hi!

In order to have fast unwinding (which doesn't use unwind info)
work properly on s390{,x}, -mbackchain is needed (similarly to
-fno-omit-frame-pointer needed everywhere and -mno-omit-leaf-frame-pointer
on x86).  Committed to trunk:

2017-02-11  Jakub Jelinek  <ja...@redhat.com>

        PR sanitizer/79341
        * g++.dg/asan/deep-stack-uaf-1.C: New test.

--- gcc/testsuite/g++.dg/asan/deep-stack-uaf-1.C.jj     2014-11-20 
08:32:13.000000000 +0100
+++ gcc/testsuite/g++.dg/asan/deep-stack-uaf-1.C        2017-02-11 
19:35:50.776542716 +0100
@@ -5,6 +5,7 @@
 // { dg-set-target-env-var ASAN_OPTIONS "malloc_context_size=120:redzone=512" }
 // { dg-options "-fno-omit-frame-pointer -fno-optimize-sibling-calls" }
 // { dg-additional-options "-mno-omit-leaf-frame-pointer" { target { i?86-*-* 
x86_64-*-* } } }
+// { dg-additional-options "-mbackchain" { target { s390*-*-* } } }
 // { dg-shouldfail "asan" }
 
 #include <stdlib.h>


        Jakub