It looks like RTL peep2 can leave unreachable blocks around by
missing to check the currently write-only variable
peep2_do_cleanup_cfg at the end and cleanup the CFG in that
case.
Fixed like so, bootstrap and regtest scheduled on
x86_64-unknown-linux-gnu.
Richard.
2014-08-13 Richard Biener <rguent...@suse.de>
PR rtl-optimization/62079
* recog.c (peephole2_optimize): If peep2_do_cleanup_cfg
run cleanup_cfg.
* g++.dg/pr62079.C: New testcase.
Index: gcc/recog.c
===================================================================
--- gcc/recog.c (revision 213909)
+++ gcc/recog.c (working copy)
@@ -3553,6 +3553,8 @@ peephole2_optimize (void)
BITMAP_FREE (live);
if (peep2_do_rebuild_jump_labels)
rebuild_jump_labels (get_insns ());
+ if (peep2_do_cleanup_cfg)
+ cleanup_cfg (CLEANUP_CFG_CHANGED);
}
#endif /* HAVE_peephole2 */
Index: gcc/testsuite/g++.dg/pr62079.C
===================================================================
--- gcc/testsuite/g++.dg/pr62079.C (revision 0)
+++ gcc/testsuite/g++.dg/pr62079.C (working copy)
@@ -0,0 +1,78 @@
+// { dg-do compile }
+// { dg-options "-std=c++11 -O2 -fnon-call-exceptions" }
+
+template < typename > class allocator;
+
+template < class _CharT > struct char_traits;
+template < typename _CharT, typename _Traits = char_traits < _CharT >,
+ typename _Alloc = allocator < _CharT > >class basic_string;
+typedef basic_string < char >string;
+
+template < typename _Tp > class new_allocator
+{
+ template < typename _Tp1 > struct rebind
+ {
+ typedef new_allocator < _Tp1 > other;
+ };
+};
+
+template < typename _Tp > using __allocator_base = new_allocator < _Tp >;
+template < typename _Tp > class allocator:public __allocator_base < _Tp >
+{
+};
+
+template < typename _CharT, typename _Traits, typename _Alloc >
+ class basic_string
+{
+public:
+ basic_string (const _CharT * __s, const _Alloc & __a = _Alloc ());
+ ~basic_string ()noexcept;
+};
+
+template < typename T > struct add_reference
+{
+ typedef T & type;
+};
+
+template < typename ... Values > class tuple;
+template <> class tuple <>
+{
+};
+
+template < typename Head, typename ... Tail > class tuple < Head, Tail ...
>:private tuple <
+ Tail ...
+ >
+{
+ typedef tuple < Tail ... >inherited;
+public:
+ template < typename ... VValues >
+ tuple (const tuple < VValues ... >&other):inherited (other.tail ()),
+ m_head (other.head ())
+ {
+ }
+ typename add_reference < const Head >::type head () const
+ {
+ return m_head;
+ }
+ const inherited & tail () const
+ {
+ return *this;
+ }
+ Head m_head;
+};
+
+template < typename T > struct make_tuple_result
+{
+ typedef T type;
+};
+
+template < typename ... Values >
+ tuple < typename make_tuple_result <
+ Values >::type ... >make_tuple (const Values & ... values);
+
+int
+main ()
+{
+ tuple < int, float, string > t3c =
+ make_tuple (17, 2.718281828, string ("Fun"));
+}
