From 3feb128fadfe1f496dd5d59116221e07fe019e27 Mon Sep 17 00:00:00 2001
From: Jason Merrill <jason@redhat.com>
Date: Sun, 21 Dec 2008 16:01:48 -0500
Subject: [PATCH] re PR c++/38597 ([c++0x] ICE when auto return type function
 given as argument to function template)

        PR c++/38597
        * name-lookup.c (arg_assoc_type): Handle DECLTYPE_TYPE.

From-SVN: r142868
---
 gcc/cp/ChangeLog                    |  5 +++++
 gcc/cp/mangle.c                     |  8 ++++----
 gcc/cp/name-lookup.c                |  1 +
 gcc/testsuite/ChangeLog             |  5 +++++
 gcc/testsuite/g++.dg/cpp0x/auto13.C | 11 +++++++++++
 5 files changed, 26 insertions(+), 4 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp0x/auto13.C

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 19af86ccde6d..94e1a7cd2c10 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,8 @@
+2008-12-21  Jason Merrill  <jason@redhat.com>
+
+	PR c++/38597
+	* name-lookup.c (arg_assoc_type): Handle DECLTYPE_TYPE.
+
 2008-12-20  Jakub Jelinek  <jakub@redhat.com>
 	    Manuel López-Ibáñez  <manu@gcc.gnu.org>
 
diff --git a/gcc/cp/mangle.c b/gcc/cp/mangle.c
index 1ec27c1ffcd7..a7b466217ebd 100644
--- a/gcc/cp/mangle.c
+++ b/gcc/cp/mangle.c
@@ -2348,12 +2348,12 @@ write_expression (tree expr)
 
 	case CAST_EXPR:
 	  write_type (TREE_TYPE (expr));
+	  /* There is no way to mangle a zero-operand cast like
+	     "T()".  */
 	  if (!TREE_OPERAND (expr, 0))
-	    /* "T()" is mangled as "T(void)".  */
-	    write_char ('v');
+	    sorry ("zero-operand casts cannot be mangled due to a defect "
+		   "in the C++ ABI");
 	  else if (list_length (TREE_OPERAND (expr, 0)) > 1)
-	    /* FIXME the above hack for T() needs to be replaced with
-	       something more general.  */
 	    sorry ("mangling function-style cast with more than one argument");
 	  else
 	    write_expression (TREE_VALUE (TREE_OPERAND (expr, 0)));
diff --git a/gcc/cp/name-lookup.c b/gcc/cp/name-lookup.c
index b5d14b3b39c4..4c06afdafacf 100644
--- a/gcc/cp/name-lookup.c
+++ b/gcc/cp/name-lookup.c
@@ -4701,6 +4701,7 @@ arg_assoc_type (struct arg_lookup *k, tree type)
     case VECTOR_TYPE:
     case BOOLEAN_TYPE:
     case FIXED_POINT_TYPE:
+    case DECLTYPE_TYPE:
       return false;
     case RECORD_TYPE:
       if (TYPE_PTRMEMFUNC_P (type))
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 11feb22bd969..88d4c38b89f7 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2008-12-21  Jason Merrill  <jason@redhat.com>
+
+	PR c++/38597
+	* g++.dg/cpp0x/auto13.C: New test.
+
 2008-12-20  Jakub Jelinek  <jakub@redhat.com>
 	    Manuel López-Ibáñez  <manu@gcc.gnu.org>
 
diff --git a/gcc/testsuite/g++.dg/cpp0x/auto13.C b/gcc/testsuite/g++.dg/cpp0x/auto13.C
new file mode 100644
index 000000000000..dc7e35aabaa4
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/auto13.C
@@ -0,0 +1,11 @@
+// PR c++/38597
+// { dg-options "-std=c++0x" }
+
+template<class T, class U>
+auto f(T,U) -> decltype(T() + U())
+{ return T() + U(); }
+
+template<class T> void g(T){}
+
+int main() { g(f); }		// { dg-error "no matching function" }
+