On 11/09/2016 02:47 PM, Martin Liška wrote:
> On 11/09/2016 02:29 PM, Jakub Jelinek wrote:
>> On Wed, Nov 09, 2016 at 02:16:45PM +0100, Martin Liška wrote:
>>> As shown in the attached test-case, the assert cannot always be true.
>>> Patch can bootstrap on ppc64le-redhat-linux and survives regression tests.
>>>
>>> Ready to be installed?
>>> Martin
>>
>>> >From b55459461f3f7396a094be6801082715ddb4b30d Mon Sep 17 00:00:00 2001
>>> From: marxin <mli...@suse.cz>
>>> Date: Wed, 9 Nov 2016 11:52:00 +0100
>>> Subject: [PATCH] Remove unneeded gcc_assert in gimplifier (PR
>>> sanitizer/78270)
>>>
>>> gcc/ChangeLog:
>>>
>>> 2016-11-09 Martin Liska <mli...@suse.cz>
>>>
>>> PR sanitizer/78270
>>> * gimplify.c (gimplify_switch_expr):
>>
>> No description on what you've changed.
>>
>> That said, I'm not 100% sure it is the right fix.
>> As the testcase shows, for switch without GIMPLE_BIND wrapping the body
>> we can have variables that are in scope from the switch onwards.
>> I bet we could also have variables that go out of scope, say if in the
>> compound literal's initializer there is ({ ... }) that declares variables.
>> I doubt you can have a valid case/default label in those though, so
>> perhaps it would be simpler not to create live_switch_vars at all
>> if SWITCH_BODY is not a BIND_EXPR?
>
> I like the approach you introduced! I'll re-trigger regression tests and
> send a newer version of patch.
>
> Martin
Sending the patch.
Patch can bootstrap on ppc64le-redhat-linux and survives regression tests.
Ready to be installed?
Martin
>
>>
>> Jakub
>>
>
>From fb4b852a17656309e6acfb8da97cf9bce4b3b176 Mon Sep 17 00:00:00 2001
From: marxin <mli...@suse.cz>
Date: Wed, 9 Nov 2016 11:52:00 +0100
Subject: [PATCH] Create live_switch_vars conditionally (PR sanitizer/78270)
gcc/testsuite/ChangeLog:
2016-11-09 Martin Liska <mli...@suse.cz>
* gcc.dg/asan/pr78269.c: New test.
gcc/ChangeLog:
2016-11-09 Martin Liska <mli...@suse.cz>
* gimplify.c (gimplify_switch_expr): Create live_switch_vars
only when SWITCH_BODY is a BIND_EXPR.
---
gcc/gimplify.c | 20 +++++++++++++++-----
gcc/testsuite/gcc.dg/asan/pr78269.c | 13 +++++++++++++
2 files changed, 28 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/asan/pr78269.c
diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index d392450..da60c05 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -2241,7 +2241,7 @@ gimplify_switch_expr (tree *expr_p, gimple_seq *pre_p)
{
vec<tree> labels;
vec<tree> saved_labels;
- hash_set<tree> *saved_live_switch_vars;
+ hash_set<tree> *saved_live_switch_vars = NULL;
tree default_case = NULL_TREE;
gswitch *switch_stmt;
@@ -2253,8 +2253,14 @@ gimplify_switch_expr (tree *expr_p, gimple_seq *pre_p)
labels. Save all the things from the switch body to append after. */
saved_labels = gimplify_ctxp->case_labels;
gimplify_ctxp->case_labels.create (8);
- saved_live_switch_vars = gimplify_ctxp->live_switch_vars;
- gimplify_ctxp->live_switch_vars = new hash_set<tree> (4);
+
+ /* Do not create live_switch_vars if SWITCH_BODY is not a BIND_EXPR. */
+ if (TREE_CODE (SWITCH_BODY (switch_expr)) == BIND_EXPR)
+ {
+ saved_live_switch_vars = gimplify_ctxp->live_switch_vars;
+ gimplify_ctxp->live_switch_vars = new hash_set<tree> (4);
+ }
+
bool old_in_switch_expr = gimplify_ctxp->in_switch_expr;
gimplify_ctxp->in_switch_expr = true;
@@ -2269,8 +2275,12 @@ gimplify_switch_expr (tree *expr_p, gimple_seq *pre_p)
labels = gimplify_ctxp->case_labels;
gimplify_ctxp->case_labels = saved_labels;
- gcc_assert (gimplify_ctxp->live_switch_vars->elements () == 0);
- delete gimplify_ctxp->live_switch_vars;
+
+ if (gimplify_ctxp->live_switch_vars)
+ {
+ gcc_assert (gimplify_ctxp->live_switch_vars->elements () == 0);
+ delete gimplify_ctxp->live_switch_vars;
+ }
gimplify_ctxp->live_switch_vars = saved_live_switch_vars;
preprocess_case_label_vec_for_gimple (labels, index_type,
diff --git a/gcc/testsuite/gcc.dg/asan/pr78269.c b/gcc/testsuite/gcc.dg/asan/pr78269.c
new file mode 100644
index 0000000..55840b0
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/asan/pr78269.c
@@ -0,0 +1,13 @@
+// { dg-do compile }
+// { dg-additional-options "-Wno-switch-unreachable" }
+
+typedef struct
+{
+} bdaddr_t;
+
+int a;
+void fn1 ()
+{
+ switch (a)
+ &(bdaddr_t){};
+}
--
2.10.1
