This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
C++ PATCH for c++/58466 (ICE with variadics and partial specialization)
- From: Jason Merrill <jason at redhat dot com>
- To: gcc-patches List <gcc-patches at gcc dot gnu dot org>
- Date: Wed, 29 Jan 2014 15:53:57 -0500
- Subject: C++ PATCH for c++/58466 (ICE with variadics and partial specialization)
- Authentication-results: sourceware.org; auth=none
Here the problem was that when we built up A<'X'> the arguments to A
were 'X' and the empty set for the parameter pack. When we then use
that to deduce the arguments for C, we got confused by the empty set and
tried to treat it as another argument, leading to bad times. Fixed by
calling expand_template_argument_pack in unify_pack_expansion.
Tested x86_64-pc-linux-gnu, applying to trunk.
commit 8494bec4e85a987375b3e1044574ddb89fa6e120
Author: Jason Merrill <jason@redhat.com>
Date: Wed Jan 29 15:37:41 2014 -0500
PR c++/58466
* pt.c (unify_pack_expansion): Call expand_template_argument_pack.
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 943255d..9be9171 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -16897,6 +16897,9 @@ unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
tree pattern = PACK_EXPANSION_PATTERN (parm);
tree pack, packs = NULL_TREE;
int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
+
+ packed_args = expand_template_argument_pack (packed_args);
+
int len = TREE_VEC_LENGTH (packed_args);
/* Determine the parameter packs we will be deducing from the
diff --git a/gcc/testsuite/g++.dg/cpp0x/variadic147.C b/gcc/testsuite/g++.dg/cpp0x/variadic147.C
new file mode 100644
index 0000000..7f606d8
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/variadic147.C
@@ -0,0 +1,10 @@
+// PR c++/58466
+// { dg-require-effective-target c++11 }
+
+template<char, char...> struct A;
+
+template<typename> struct B;
+
+template<char... C> struct B<A<C...>> {};
+
+B<A<'X'>> b;