[PATCH] Don't ICE on empty bbs with no successors in EH opt (PR middle-end/57499)

2014-02-05 Thread Jakub Jelinek 
Hi!

As the testcase shows, invalid use of noreturn attribute (which we diagnose)
can result in in empty bb with no successors.  This patch fixes
cleanup_empty_eh not to ICE on these.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2014-02-04  Jakub Jelinek  ja...@redhat.com

PR middle-end/57499
* tree-eh.c (cleanup_empty_eh): Bail out on totally empty
bb with no successors.

* g++.dg/torture/pr57499.C: New test.

--- gcc/tree-eh.c.jj2014-01-31 22:22:09.0 +0100
+++ gcc/tree-eh.c   2014-02-04 12:35:05.611066852 +0100
@@ -4396,8 +4396,11 @@ cleanup_empty_eh (eh_landing_pad lp)
   /* If the block is totally empty, look for more unsplitting cases.  */
   if (gsi_end_p (gsi))
 {
-  /* For the degenerate case of an infinite loop bail out.  */
-  if (infinite_empty_loop_p (e_out))
+  /* For the degenerate case of an infinite loop bail out.
+If bb has no successors and is totally empty, which can happen e.g.
+because of incorrect noreturn attribute, bail out too.  */
+  if (e_out == NULL
+ || infinite_empty_loop_p (e_out))
return ret;
 
   return ret | cleanup_empty_eh_unsplit (bb, e_out, lp);
--- gcc/testsuite/g++.dg/torture/pr57499.C.jj   2014-02-04 12:52:10.241846755 
+0100
+++ gcc/testsuite/g++.dg/torture/pr57499.C  2014-02-04 12:51:51.0 
+0100
@@ -0,0 +1,14 @@
+// PR middle-end/57499
+// { dg-do compile }
+
+struct S
+{
+  ~S () __attribute__ ((noreturn)) {} // { dg-warning function does return }
+};
+
+void
+foo ()
+{
+  S s;
+  throw 1;
+}

Jakub

Re: [PATCH] Don't ICE on empty bbs with no successors in EH opt (PR middle-end/57499)

2014-02-05 Thread Richard Biener 
On Wed, 5 Feb 2014, Jakub Jelinek wrote:

 Hi!
 
 As the testcase shows, invalid use of noreturn attribute (which we diagnose)
 can result in in empty bb with no successors.  This patch fixes
 cleanup_empty_eh not to ICE on these.
 
 Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

Ok.

Thanks,
Richard.

 2014-02-04  Jakub Jelinek  ja...@redhat.com
 
   PR middle-end/57499
   * tree-eh.c (cleanup_empty_eh): Bail out on totally empty
   bb with no successors.
 
   * g++.dg/torture/pr57499.C: New test.
 
 --- gcc/tree-eh.c.jj  2014-01-31 22:22:09.0 +0100
 +++ gcc/tree-eh.c 2014-02-04 12:35:05.611066852 +0100
 @@ -4396,8 +4396,11 @@ cleanup_empty_eh (eh_landing_pad lp)
/* If the block is totally empty, look for more unsplitting cases.  */
if (gsi_end_p (gsi))
  {
 -  /* For the degenerate case of an infinite loop bail out.  */
 -  if (infinite_empty_loop_p (e_out))
 +  /* For the degenerate case of an infinite loop bail out.
 +  If bb has no successors and is totally empty, which can happen e.g.
 +  because of incorrect noreturn attribute, bail out too.  */
 +  if (e_out == NULL
 +   || infinite_empty_loop_p (e_out))
   return ret;
  
return ret | cleanup_empty_eh_unsplit (bb, e_out, lp);
 --- gcc/testsuite/g++.dg/torture/pr57499.C.jj 2014-02-04 12:52:10.241846755 
 +0100
 +++ gcc/testsuite/g++.dg/torture/pr57499.C2014-02-04 12:51:51.0 
 +0100
 @@ -0,0 +1,14 @@
 +// PR middle-end/57499
 +// { dg-do compile }
 +
 +struct S
 +{
 +  ~S () __attribute__ ((noreturn)) {} // { dg-warning function does return 
 }
 +};
 +
 +void
 +foo ()
 +{
 +  S s;
 +  throw 1;
 +}
 
   Jakub
 
 

-- 
Richard Biener rguent...@suse.de
SUSE / SUSE Labs
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