re PR c++/71210 (internal compiler error: in assign_temp, at function.c:961)

	PR c++/71210
	* gimple-fold.c (gimple_fold_call): Do not remove lhs of noreturn
	calls if the LHS is variable length or has addressable type.
	If targets[0]->decl is a noreturn call with void return type and
	zero arguments, adjust fntype and remove lhs in that case.

	* g++.dg/opt/pr71210-1.C: New test.
	* g++.dg/opt/pr71210-2.C: New test.

From-SVN: r236506

5 files changed, 66 insertions, 2 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f874a6c..403c01f 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2016-05-20  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/71210
+	* gimple-fold.c (gimple_fold_call): Do not remove lhs of noreturn
+	calls if the LHS is variable length or has addressable type.
+	If targets[0]->decl is a noreturn call with void return type and
+	zero arguments, adjust fntype and remove lhs in that case.
+
 2016-05-20  Marc Glisse  <marc.glisse@inria.fr>
 
 	PR tree-optimization/71079
diff --git a/gcc/gimple-fold.c b/gcc/gimple-fold.c
index d3968e9..858f484 100644
--- a/gcc/gimple-fold.c
+++ b/gcc/gimple-fold.c
@@ -3039,10 +3039,25 @@ gimple_fold_call (gimple_stmt_iterator *gsi, bool inplace)
 		}
 	      if (targets.length () == 1)
 		{
-		  gimple_call_set_fndecl (stmt, targets[0]->decl);
+		  tree fndecl = targets[0]->decl;
+		  gimple_call_set_fndecl (stmt, fndecl);
 		  changed = true;
+		  /* If changing the call to __cxa_pure_virtual
+		     or similar noreturn function, adjust gimple_call_fntype
+		     too.  */
+		  if ((gimple_call_flags (stmt) & ECF_NORETURN)
+		      && VOID_TYPE_P (TREE_TYPE (TREE_TYPE (fndecl)))
+		      && TYPE_ARG_TYPES (TREE_TYPE (fndecl))
+		      && (TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (fndecl)))
+			  == void_type_node))
+		    gimple_call_set_fntype (stmt, TREE_TYPE (fndecl));
 		  /* If the call becomes noreturn, remove the lhs.  */
-		  if (lhs && (gimple_call_flags (stmt) & ECF_NORETURN))
+		  if (lhs
+		      && (gimple_call_flags (stmt) & ECF_NORETURN)
+		      && (VOID_TYPE_P (TREE_TYPE (gimple_call_fntype (stmt)))
+			  || ((TREE_CODE (TYPE_SIZE_UNIT (TREE_TYPE (lhs)))
+			       == INTEGER_CST)
+			      && !TREE_ADDRESSABLE (TREE_TYPE (lhs)))))
 		    {
 		      if (TREE_CODE (lhs) == SSA_NAME)
 			{
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 94080ab..fe4727a 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,9 @@
 2016-05-20  Jakub Jelinek  <jakub@redhat.com>
 
+	PR c++/71210
+	* g++.dg/opt/pr71210-1.C: New test.
+	* g++.dg/opt/pr71210-2.C: New test.
+
 	PR tree-optimization/29756
 	gcc.dg/tree-ssa/vector-6.c: Add -Wno-psabi -w to dg-options.
 	Add -msse2 for x86 and -maltivec for powerpc.  Use scan-tree-dump-times
diff --git a/gcc/testsuite/g++.dg/opt/pr71210-1.C b/gcc/testsuite/g++.dg/opt/pr71210-1.C
new file mode 100644
index 0000000..03b1fb5
--- /dev/null
+++ b/gcc/testsuite/g++.dg/opt/pr71210-1.C
@@ -0,0 +1,14 @@
+// PR c++/71210
+// { dg-do compile }
+// { dg-options "-O2" }
+
+#include <typeinfo>
+
+void f1 (const std::type_info&) __attribute__((noreturn));
+struct S1 { ~S1 (); };
+struct S2
+{
+  virtual S1 f2 () const { f1 (typeid (*this)); }
+  S1 f3 () const { return f2 (); }
+};
+void f4 () { S2 a; a.f3 (); }
diff --git a/gcc/testsuite/g++.dg/opt/pr71210-2.C b/gcc/testsuite/g++.dg/opt/pr71210-2.C
new file mode 100644
index 0000000..02a31bd
--- /dev/null
+++ b/gcc/testsuite/g++.dg/opt/pr71210-2.C
@@ -0,0 +1,23 @@
+// PR c++/71210
+// { dg-do compile }
+// { dg-options "-O2" }
+
+struct C { int a; int b; C (); ~C (); };
+
+namespace
+{
+  struct A
+  {
+    A () {}
+    virtual C bar (int) = 0;
+    C baz (int x) { return bar (x); }
+  };
+}
+
+A *a;
+
+void
+foo ()
+{
+  C c = a->baz (0);
+}