https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114954
Bug ID: 114954
Summary: [modules] ICE in write_class_def with templated union
type
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: nshead at gcc dot gnu.org
Blocks: 103524
Target Milestone: ---
The following sample crashes on trunk:
export module main;
template <int N>
union U {
private:
char a[N + 1];
int b;
};
U<4> p;
With 'g++ -fmodules-ts -S main.cpp':
~/ice/main.cpp:1:8: internal compiler error: in write_class_def, at
cp/module.cc:12118
1 | export module main;
| ^~~~~~
0x1010c67 write_class_def
../../gcc/gcc/cp/module.cc:12118
0x1014d91 write_definition
../../gcc/gcc/cp/module.cc:12731
0x101880e depset::hash::find_dependencies(module_state*)
../../gcc/gcc/cp/module.cc:13640
0x1026a62 module_state::write_begin(elf_out*, cpp_reader*,
module_state_config&, unsigned int&)
../../gcc/gcc/cp/module.cc:18253
0x102e39f finish_module_processing(cpp_reader*)
../../gcc/gcc/cp/module.cc:20693
0xf50556 c_parse_final_cleanups()
../../gcc/gcc/cp/decl2.cc:5393
0x131e75f c_common_parse_file()
../../gcc/gcc/c-family/c-opts.cc:1329
The assertion that fails is
/* Every class but __as_base has a type-specific. */
gcc_checking_assert (!TYPE_LANG_SPECIFIC (type) == IS_FAKE_BASE_TYPE (type));
The issue looks to be that a union `__as_base` type doesn't satisfy the
'IS_FAKE_BASE_TYPE', which only applies to RECORD_TYPEs.
Referenced Bugs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103524
[Bug 103524] [meta-bug] modules issue
