| Message ID | 0c9de9bb-a232-07d4-302d-c59108484ccf@suse.cz |
|---|---|
| State | New |
| Headers | show |
On Thu, Mar 02, 2017 at 06:49:32PM +0100, Martin Liška wrote: > It can happen with inlining and -fno-tree-dce that VAR_DECL for a SSA > NAME was removed and thus the poisoning should not have any usage. > > Patch can bootstrap on ppc64le-redhat-linux and survives regression tests. > > Ready to be installed? > Martin > >From d8aa72dc1d696f5500c00b6c2f532f2a87cf58d2 Mon Sep 17 00:00:00 2001 > From: marxin <mliska@suse.cz> > Date: Thu, 2 Mar 2017 11:55:00 +0100 > Subject: [PATCH] Fix ICE in use-after-scope w/ -fno-tree-dce (PR > sanitize/79783). > > gcc/ChangeLog: > > 2017-03-02 Martin Liska <mliska@suse.cz> > > PR sanitize/79783 > * asan.c (asan_expand_poison_ifn): Do not expand ASAN_POISON > when having a SSA NAME w/o VAR_DECL assigned to it. > > gcc/testsuite/ChangeLog: > > 2017-03-02 Martin Liska <mliska@suse.cz> > > PR sanitize/79783 > * g++.dg/asan/pr79783.C: New test. > --- > gcc/asan.c | 5 ++++- > gcc/testsuite/g++.dg/asan/pr79783.C | 19 +++++++++++++++++++ > 2 files changed, 23 insertions(+), 1 deletion(-) > create mode 100644 gcc/testsuite/g++.dg/asan/pr79783.C > > diff --git a/gcc/asan.c b/gcc/asan.c > index 6cdd59b7ea7..307423ced03 100644 > --- a/gcc/asan.c > +++ b/gcc/asan.c > @@ -3107,7 +3107,10 @@ asan_expand_poison_ifn (gimple_stmt_iterator *iter, > { > gimple *g = gsi_stmt (*iter); > tree poisoned_var = gimple_call_lhs (g); > - if (!poisoned_var) > + > + /* It can happen with inlining and -fno-tree-dce that VAR_DECL for a SSA > + NAME was removed and thus the poisoning should not have any usage. */ > + if (!poisoned_var || SSA_NAME_VAR (poisoned_var) == NULL_TREE) I wonder if it wouldn't be better to do: if (!poisoned_var || has_zero_uses (poisoned_var)) perhaps with -fno-tree-dce we could end up with SSA_NAME_VAR being non-NULL, yet no uses; in that case there is nothing to warn about. On the other side, in theory we could also end up with anonymous SSA_NAME and some uses - in that case perhaps it would be better to warn. So do: if (SSA_NAME_VAR (poisoned_var) == NULL_TREE) SSA_NAME_VAR (poisoned_var) = create_tmp_var (TREE_TYPE (poisoned_var)); tree shadow_var = create_asan_shadow_var (SSA_NAME_VAR (poisoned_var), shadow_vars_mapping); or so? We'll need SSA_NAME_VAR non-NULL so that we can use a default def later. Jakub
From d8aa72dc1d696f5500c00b6c2f532f2a87cf58d2 Mon Sep 17 00:00:00 2001 From: marxin <mliska@suse.cz> Date: Thu, 2 Mar 2017 11:55:00 +0100 Subject: [PATCH] Fix ICE in use-after-scope w/ -fno-tree-dce (PR sanitize/79783). gcc/ChangeLog: 2017-03-02 Martin Liska <mliska@suse.cz> PR sanitize/79783 * asan.c (asan_expand_poison_ifn): Do not expand ASAN_POISON when having a SSA NAME w/o VAR_DECL assigned to it. gcc/testsuite/ChangeLog: 2017-03-02 Martin Liska <mliska@suse.cz> PR sanitize/79783 * g++.dg/asan/pr79783.C: New test. --- gcc/asan.c | 5 ++++- gcc/testsuite/g++.dg/asan/pr79783.C | 19 +++++++++++++++++++ 2 files changed, 23 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/g++.dg/asan/pr79783.C diff --git a/gcc/asan.c b/gcc/asan.c index 6cdd59b7ea7..307423ced03 100644 --- a/gcc/asan.c +++ b/gcc/asan.c @@ -3107,7 +3107,10 @@ asan_expand_poison_ifn (gimple_stmt_iterator *iter, { gimple *g = gsi_stmt (*iter); tree poisoned_var = gimple_call_lhs (g); - if (!poisoned_var) + + /* It can happen with inlining and -fno-tree-dce that VAR_DECL for a SSA + NAME was removed and thus the poisoning should not have any usage. */ + if (!poisoned_var || SSA_NAME_VAR (poisoned_var) == NULL_TREE) { gsi_remove (iter, true); return true; diff --git a/gcc/testsuite/g++.dg/asan/pr79783.C b/gcc/testsuite/g++.dg/asan/pr79783.C new file mode 100644 index 00000000000..939f60b2819 --- /dev/null +++ b/gcc/testsuite/g++.dg/asan/pr79783.C @@ -0,0 +1,19 @@ +// PR sanitizer/79783 +// { dg-options "-fno-tree-dce" } + +struct A +{ + static void foo(const char&) {} +}; + +struct B +{ + B() { A::foo(char()); } +}; + +struct C +{ + virtual void bar() const { B b; } +}; + +C c; -- 2.11.1