Hi,
this (and 55786, which is a Dup) is an ICE on invalid regression in
4.7/4.8. The problem is that for such broken input,
check_elaborated_type_specifier is called by
cp_parser_elaborated_type_specifier with a DECL which has a nul
TREE_TYPE, a TEMPLATE_ID_EXPR actually, and therefore immediately
crashes on TREE_CODE (type) == TEMPLATE_TYPE_PARM.
In comparison, 4_6-branch, instead of calling
check_elaborated_type_specifier, has cp_parser_elaborated_type_specifier
simply doing type = TREE_TYPE (decl), thus it seems we can cure the
regression in a straightforward and safe way by simply checking that
TREE_TYPE (decl) is not nul at the beginning of
check_elaborated_type_specifier. In this way the error messages are also
exactly the same produced by 4_6.
Tested x86_64-linux.
Thanks,
Paolo.
//////////////////////
/cp
2013-03-05 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/56534
* decl.c (check_elaborated_type_specifier): Check for NULL_TREE
as TREE_TYPE (decl).
/testsuite
2013-03-05 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/56534
* g++.dg/template/crash115.C: New.
Index: cp/decl.c
===================================================================
--- cp/decl.c (revision 196465)
+++ cp/decl.c (working copy)
@@ -11725,6 +11725,8 @@ check_elaborated_type_specifier (enum tag_types ta
decl = TYPE_NAME (TREE_TYPE (decl));
type = TREE_TYPE (decl);
+ if (!type)
+ return NULL_TREE;
/* Check TEMPLATE_TYPE_PARM first because DECL_IMPLICIT_TYPEDEF_P
is false for this case as well. */
Index: testsuite/g++.dg/template/crash115.C
===================================================================
--- testsuite/g++.dg/template/crash115.C (revision 0)
+++ testsuite/g++.dg/template/crash115.C (working copy)
@@ -0,0 +1,3 @@
+// PR c++/56534
+
+template < struct template rebind < > // { dg-error "expected" }
