https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118192
Bug ID: 118192
Summary: ICE: in build_data_member_initialization, at
cp/constexpr.cc:453
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 invalid code triggers an ICE on x86-64 gcc trunk:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
template<int>
struct base
{
int y;
base() = delete;
constexpr base(int a) : base{}
{ y = a; }
};
struct foo : base<1>
{
constexpr foo(int a) : base<1>{a}
{
}
};
int main()
{
constexpr foo bar1{1};
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
It's invalid because the ` constexpr base(int a) : base{}` tries to call the
deleted default ctor of `base`. Please note that the crash will not appear if
the ctor does nothing in its function body like:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
template<int>
struct base
{
base() = delete;
constexpr base(int a) : base{}{}
};
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Please check https://godbolt.org/z/8Pj76MdoT for more information.
$ g++ -freport-bug of3468.cpp
<source>: In instantiation of 'constexpr base<<anonymous> >::base(int) [with
int <anonymous> = 1]':
<source>:12:35: required from here
12 | constexpr foo(int a) : base<1>{a}
| ^
<source>:19:23: in 'constexpr' expansion of '((foo*)(& bar1))->foo::foo(1)'
<source>:6:32: error: use of deleted function 'base<<anonymous> >::base() [with
int <anonymous> = 1]'
6 | constexpr base(int a) : base{}
| ^
<source>:5:3: note: declared here
5 | base() = delete;
| ^~~~
<source>:6:32: note: use '-fdiagnostics-all-candidates' to display considered
candidates
6 | constexpr base(int a) : base{}
| ^
<source>: In function 'int main()':
<source>:19:23: in 'constexpr' expansion of '((foo*)(& bar1))->foo::foo(1)'
<source>:12:35: error: 'constexpr base<<anonymous> >::base(int) [with int
<anonymous> = 1]' called in a constant expression
12 | constexpr foo(int a) : base<1>{a}
| ^
<source>:6:13: note: 'constexpr base<<anonymous> >::base(int) [with int
<anonymous> = 1]' is not usable as a 'constexpr' function because:
6 | constexpr base(int a) : base{}
| ^~~~
<source>:6:13: internal compiler error: in build_data_member_initialization, at
cp/constexpr.cc:453
0x2931885 diagnostic_context::diagnostic_impl(rich_location*,
diagnostic_metadata const*, diagnostic_option_id, char const*, __va_list_tag
(*) [1], diagnostic_t)
???:0
0x2948656 internal_error(char const*, ...)
???:0
0xac9dee fancy_abort(char const*, int, char const*)
???:0
0xb42a60 explain_invalid_constexpr_fn(tree_node*)
???:0
0xdc5bde store_init_value(tree_node*, tree_node*, vec<tree_node*, va_gc,
vl_embed>**, int)
???:0
0xbbeb4e cp_finish_decl(tree_node*, tree_node*, bool, tree_node*, int,
cp_decomp*)
???:0
0xce1f2a c_parse_file()
???:0
0xe41159 c_common_parse_file()
???:0
Please submit a full bug report, with preprocessed source.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
