https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89917
Bug ID: 89917
Summary: [8/9 Regression] ICE with lambda in variadic template
hierarchy
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Keywords: ice-on-valid-code
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: reichelt at gcc dot gnu.org
Target Milestone: ---
The following valid code snippet triggers an ICE since GCC 8.2.0,
so this is a regression on the GCC 8 branch.
=============================================
struct A
{
A(...);
};
template<typename... T> struct B : T...
{
B() : T([]{})... {}
};
B<A> b;
=============================================
bug.cc: In instantiation of 'B<T>::B() [with T = {A}]':
bug.cc:11:6: required from here
bug.cc:8:16: internal compiler error: tree check: expected tree_vec, have
type_pack_expansion in tsubst_initializer_list, at cp/pt.c:24915
8 | B() : T([]{})... {}
| ^~~
0x7da784 tree_check_failed(tree_node const*, char const*, int, char const*,
...)
../../gcc/gcc/tree.c:9881
0x65d072 tree_check(tree_node*, char const*, int, char const*, tree_code)
../../gcc/gcc/tree.h:3176
0x65d072 tsubst_initializer_list
../../gcc/gcc/cp/pt.c:24915
0x9ff648 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/gcc/cp/pt.c:16981
0x9ff95d tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/gcc/cp/pt.c:16976
0x9fea39 tsubst_expr(tree_node*, tree_node*, int, tree_node*, bool)
../../gcc/gcc/cp/pt.c:17277
0x9fe3b8 instantiate_decl(tree_node*, bool, bool)
../../gcc/gcc/cp/pt.c:24730
0xa244db instantiate_pending_templates(int)
../../gcc/gcc/cp/pt.c:24846
0x941600 c_parse_final_cleanups()
../../gcc/gcc/cp/decl2.c:4818
Please submit a full bug report, [etc.]
