https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106052
Bug ID: 106052
Summary: ICE with -Wmismatched-tags with partially specialized
friend struct of self type
Product: gcc
Version: 10.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: beardsley.matt.j at gmail dot com
Target Milestone: ---
The following uses gcc built from a fresh repo that I just cloned earlier today
(default build settings)
tmp.cpp:
template <typename T1, typename T2>
struct S {
template <typename, typename>
struct S2;
template <typename Type>
struct S2<Type, bool> {};
friend struct S2<S<T1, T2>, bool>;
};
No ICE with warning off:
$ g++ -c tmp.cpp -o /dev/null -Wno-mismatched-tags
(no output)
ICE with warning on:
$ g++ -c tmp.cpp -o /dev/null -Wmismatched-tags
tmp.cpp: In substitution of ‘template<class Type> struct S<T1, T2>::S2<Type,
bool> [with Type = S<T1, T2>]’:
tmp.cpp:10:2: required from here
tmp.cpp:10:2: internal compiler error: tree check: accessed elt 2 of ‘tree_vec’
with 1 elts in tsubst, at cp/pt.cc:15831
10 | };
| ^
0x8ae378 tree_vec_elt_check_failed(int, int, char const*, int, char const*)
../.././gcc/tree.cc:9016
0x9d5d11 tree_vec_elt_check(tree_node*, int, char const*, int, char const*)
../.././gcc/tree.h:3737
0xb71967 tsubst(tree_node*, tree_node*, int, tree_node*)
../.././gcc/cp/pt.cc:15831
0xb7ff0e tsubst_template_args(tree_node*, tree_node*, int, tree_node*)
../.././gcc/cp/pt.cc:13580
0xb80132 tsubst_template_args(tree_node*, tree_node*, int, tree_node*)
../.././gcc/cp/pt.cc:13562
0xb6eca7 get_partial_spec_bindings
../.././gcc/cp/pt.cc:25457
0xb6f15b most_specialized_partial_spec(tree_node*, int)
../.././gcc/cp/pt.cc:25703
0xaf2970 specialization_of
../.././gcc/cp/parser.cc:33627
0xaf2970 class_decl_loc_t::diag_mismatched_tags(tree_node*)
../.././gcc/cp/parser.cc:33811
0xaf8db8 class_decl_loc_t::diag_mismatched_tags()
../.././gcc/cp/parser.cc:33935
0xb3c292 c_parse_file()
../.././gcc/cp/parser.cc:48376
0xc721d1 c_common_parse_file()
../.././gcc/c-family/c-opts.cc:1235
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
