https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118202
Bug ID: 118202
Summary: ICE segmentation fault when instantiating a derived
template class with default template argument and
special overloaded ctor
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: wangbopku15 at gmail dot com
Target Milestone: ---
The following code triggers an ICE on the trunk:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
template <typename=int>
class A;
template <typename=int>
class B: public A {
B();
B(A a);
};
void
FPS()
{
B b;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The default template argument values, the default ctor of `B` and the
overloaded ctor with a parameter of base type `A` are essential factors to
reproduce the bug.
https://godbolt.org/z/b6n34sYEh
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
<source>:4:19: error: expected class-name before '{' token [-Wtemplate-body]
4 | class B: public A {
| ^
<source>:6:7: error: missing template argument list after 'A'; template
placeholder not permitted in parameter [-Wtemplate-body]
6 | B(A a);
| ^
| <>
<source>:2:7: note: 'template<class> class A' declared here
2 | class A;
| ^
<source>: In function 'void FPS()':
<source>:12:5: internal compiler error: Segmentation fault
12 | B b;
| ^
0x2938075 diagnostic_context::diagnostic_impl(rich_location*,
diagnostic_metadata const*, diagnostic_option_id, char const*, __va_list_tag
(*) [1], diagnostic_t)
???:0
0x294ee76 internal_error(char const*, ...)
???:0
0xcf4a96 copy_guide_p(tree_node const*)
???:0
0xafb9e9 perform_dguide_overload_resolution(tree_node*, vec<tree_node*, va_gc,
vl_embed> const*, int)
???:0
0xd0595f do_auto_deduction(tree_node*, tree_node*, tree_node*, int,
auto_deduction_context, tree_node*, int, tree_node*)
???:0
0xbbee51 cp_finish_decl(tree_node*, tree_node*, bool, tree_node*, int,
cp_decomp*)
???:0
0xce5603 c_parse_file()
???:0
0xe450d9 c_common_parse_file()
???:0
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.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
