PR c++/60033
* pt.c (retrieve_specialization): When retrieving a capture pack from a
generic lambda, remove the lambda's own template argument list prior to
fetching the specialization.
PR c++/60033
* g++.dg/cpp1y/pr60033.C: New testcase.
---
gcc/cp/pt.c | 11 +++++++++++
gcc/testsuite/g++.dg/cpp1y/pr60033.C | 20 ++++++++++++++++++++
2 files changed, 31 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/cpp1y/pr60033.C
diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c
index 8126905..0d0b1dc 100644
--- a/gcc/cp/pt.c
+++ b/gcc/cp/pt.c
@@ -1031,6 +1031,17 @@ retrieve_specialization (tree tmpl, tree args, hashval_t
hash)
gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL
|| TREE_CODE (tmpl) == FIELD_DECL);
+ /* When retrieving a capture pack from a generic lambda, remove the lambda
+ call op's own template argument list from ARGS. Only the template
+ arguments active for the closure type should be used to retrieve the pack
+ specialization.
+ XXX: It may be that this situation can be avoided by manipulating the
field
+ XXX: type earlier. */
+ if (TREE_CODE (tmpl) == FIELD_DECL
+ && LAMBDA_FUNCTION_P (current_function_decl)
+ && template_class_depth (DECL_CONTEXT (tmpl)) != TMPL_ARGS_DEPTH (args))
+ args = strip_innermost_template_args (args, 1);
+
/* There should be as many levels of arguments as there are
levels of parameters. */
gcc_assert (TMPL_ARGS_DEPTH (args)
diff --git a/gcc/testsuite/g++.dg/cpp1y/pr60033.C
b/gcc/testsuite/g++.dg/cpp1y/pr60033.C
new file mode 100644
index 0000000..8194bec
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/pr60033.C
@@ -0,0 +1,20 @@
+// PR c++/60033
+// { dg-options -std=c++1y }
+
+template <typename... T>
+auto f(T&&... ts)
+{
+ return sizeof...(ts);
+}
+
+template <typename... T>
+auto g(T&&... ts) {
+ return [&] (auto v) {
+ return f(ts...);
+ };
+}
+
+int main()
+{
+ return g(1,2,3,4)(5) == 4 ? 0 : 1;
+}
--
1.9.0
