Hello.
Even though we enable by default asan-use-after-return parameter (when
-fsanitize=address is selected),
the runtime does not check use after return by default. I would consider it
useful to document.
It's quite similar to -fsanitize=recover and halt_on_error=0 situation: one has
to enable both
to really receive requested behavior.
Ready to be installed?
Thanks,
Martin
>From 165a90fb7a8a91e9196f641ff644b38c4e1b7f94 Mon Sep 17 00:00:00 2001
From: marxin <mli...@suse.cz>
Date: Fri, 30 Sep 2016 10:07:17 +0200
Subject: [PATCH] Enhance document of asan-use-after-return param.
gcc/ChangeLog:
2016-09-30 Martin Liska <mli...@suse.cz>
* doc/invoke.texi: Document asan-use-after-return that
it's disabled by default in runtime.
---
gcc/doc/invoke.texi | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 8a84e4f..0121560 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -10034,6 +10034,10 @@ is enabled by default when using @option{-fsanitize=address} option.
To disable use-after-return detection use
@option{--param asan-use-after-return=0}.
+Note: The check is disabled by default at runtime. To enable the check,
+you should set environment variable @env{ASAN_OPTIONS} to
+@code{detect_stack_use_after_return=1}.
+
@item asan-instrumentation-with-call-threshold
If number of memory accesses in function being instrumented
is greater or equal to this number, use callbacks instead of inline checks.
--
2.9.2
