From: Jason Merrill <jason@redhat.com>
Date: Wed, 19 May 2021 20:40:24 +0000 (-0400)
Subject: c++: ICE with using and enum [PR100659]
X-Git-Tag: releases/gcc-11.2.0~359
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8b7212ebb80e854c08274228627ce0a3061db6b0;p=thirdparty%2Fgcc.git

c++: ICE with using and enum [PR100659]

Here the code for 'using enum' is confused by the combination of a
using-decl and an enum that are not from 'using enum'; this CONST_DECL is
from the normal unscoped enum scoping.

	PR c++/100659

gcc/cp/ChangeLog:

	* cp-tree.h (CONST_DECL_USING_P): Check for null TREE_TYPE.

gcc/testsuite/ChangeLog:

	* g++.dg/parse/access13.C: New test.
---

diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index fbf33b9150ee..17ba7cbd2229 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -3529,6 +3529,7 @@ struct GTY(()) lang_decl {
    created by handle_using_decl.  */
 #define CONST_DECL_USING_P(NODE)			\
   (TREE_CODE (NODE) == CONST_DECL			\
+   && TREE_TYPE (NODE)					\
    && TREE_CODE (TREE_TYPE (NODE)) == ENUMERAL_TYPE	\
    && DECL_CONTEXT (NODE) != TREE_TYPE (NODE))
 
diff --git a/gcc/testsuite/g++.dg/parse/access13.C b/gcc/testsuite/g++.dg/parse/access13.C
new file mode 100644
index 000000000000..41463c5dde5e
--- /dev/null
+++ b/gcc/testsuite/g++.dg/parse/access13.C
@@ -0,0 +1,7 @@
+// PR c++/100659
+
+template <typename> struct A
+{
+  A::E::V;		       // { dg-warning "access decl" }
+  enum { V };		       // { dg-error "conflicts with a previous decl" }
+};