From 9c719c74a549d518bc38965e0a48f78d3d02adf0 Mon Sep 17 00:00:00 2001
From: jason <jason@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Fri, 9 Apr 2010 15:20:58 +0000
Subject: [PATCH] 	PR c++/42623 	* c-common.c
 (c_sizeof_or_alignof_type): Return error_mark_node 	for incomplete type.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@158167 138bc75d-0d04-0410-961f-82ee72b054a4
---
 gcc/ChangeLog                            |  4 ++++
 gcc/c-common.c                           |  2 +-
 gcc/testsuite/ChangeLog                  |  5 +++++
 gcc/testsuite/g++.dg/template/sizeof13.C | 17 +++++++++++++++++
 4 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/template/sizeof13.C

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 74eb521187c..2b3338e2c9a 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,9 @@
 2010-04-09  Jason Merrill  <jason@redhat.com>
 
+	PR c++/42623
+	* c-common.c (c_sizeof_or_alignof_type): Return error_mark_node
+	for incomplete type.
+
 	PR c++/41788
 	* stor-layout.c (finalize_record_size): Don't change TYPE_PACKED
 	based on a warning flag.
diff --git a/gcc/c-common.c b/gcc/c-common.c
index 32dc21e93af..5772b833df0 100644
--- a/gcc/c-common.c
+++ b/gcc/c-common.c
@@ -4390,7 +4390,7 @@ c_sizeof_or_alignof_type (location_t loc,
       if (complain)
 	error_at (loc, "invalid application of %qs to incomplete type %qT ",
 		  op_name, type);
-      value = size_zero_node;
+      return error_mark_node;
     }
   else
     {
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 51895eeccd3..ea156f67b0d 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2010-04-09  Jason Merrill  <jason@redhat.com>
+
+	PR c++/42623
+	* g++.dg/template/sizeof13.C: New.
+
 2010-04-09  Kai Tietz  <kai.tietz@onevision.com>
 
 	* g++.dg/other/pr35504.C: Add check for thiscall.
diff --git a/gcc/testsuite/g++.dg/template/sizeof13.C b/gcc/testsuite/g++.dg/template/sizeof13.C
new file mode 100644
index 00000000000..2f4a26e509d
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/sizeof13.C
@@ -0,0 +1,17 @@
+// PR c++/42623
+// We should choose f(B) because f(A<undef>) involves applying sizeof to
+// an incomplete class, so it is removed by SFINAE.
+// { dg-do link }
+
+struct undef;
+
+template <typename U, int N = sizeof(U)> struct A { A(int); };
+template <typename U> void f(A<U>);
+
+template <typename U> struct B { B(int) { } };
+template <typename U> void f(B<U>) { }
+
+int main()
+{
+  f<undef>(0);
+}
-- 
2.11.4.GIT