[PATCH] Sanitize printf functions

[Yury Gribov]

================
Comment at: asan/lit_tests/TestCases/printf-2.c:2
@@ +1,3 @@
+// RUN: %clang_asan -O2 %s -o %t
+// RUN: not %t 2>&1 | FileCheck %s
+
----------------
Kostya Serebryany wrote:
> please make these tests run in 3 modes:
>   ASAN_OPTIONS=check_printf=0
>   ASAN_OPTIONS=check_printf=1
>   ASAN_OPTIONS=""
> 
> we need to test that the flag affects the behavior and that it's default value is what we expect it to be.
> 
> (use FileCheck --check-prefix=CHECK-ON and --check-prefix=CHECK-OFF)
Ok.


http://llvm-reviews.chandlerc.com/D2480