https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103809
Bug ID: 103809
Summary: spurious reporting of structure redefinition
Product: gcc
Version: 11.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: florin at iucha dot net
Target Milestone: ---
Consider the following program:
/*********************************************************/
#include <concepts>
namespace priv
{
template<typename Value>
struct Struct {};
}
#ifdef SHOW_BUG
template<std::integral Integral>
struct priv::Struct<Integral> {};
// This way results in:
// <source>:19:14: error: redefinition of 'struct priv::Struct<Integral>'
// 19 | struct priv::Struct<Float> {};
// | ^~~~~~~~~~~~~
template<std::floating_point Float>
struct priv::Struct<Float> {};
#else
namespace priv
{
template<std::integral Integral>
struct Struct<Integral> {};
template<std::floating_point Float>
struct Struct<Float> {};
}
#endif
int main() {}
/*********************************************************/
Compiling with "g++ -std=c++20 -DSHOW_BUG" results in
<source>:19:14: error: redefinition of 'struct priv::Struct<Integral>'
19 | struct priv::Struct<Float> {};
| ^~~~~~~~~~~~~
<source>:12:14: note: previous definition of 'struct priv::Struct<Integral>'
12 | struct priv::Struct<Integral> {};
| ^~~~~~~~~~~~~~~~
ASM generation compiler returned: 1
<source>:19:14: error: redefinition of 'struct priv::Struct<Integral>'
19 | struct priv::Struct<Float> {};
| ^~~~~~~~~~~~~
<source>:12:14: note: previous definition of 'struct priv::Struct<Integral>'
12 | struct priv::Struct<Integral> {};
| ^~~~~~~~~~~~~~~~
Compiling without SHOW_BUG results in no error.
(Bug found by my colleague, Ramon Sibello).
