https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96816
Bug ID: 96816
Summary: bitset: debug mode: operator== ambiguous
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: jeanmichael.celerier at gmail dot com
Target Milestone: ---
Hello,
Given the following code:
```
#define _GLIBCXX_DEBUG 1
#include <bitset>
std::bitset<3> a, b;
bool test = (a == b);
```
clang gives the following error:
```
$ clang++ -c foo.cpp -std=c++20
In file included from foo.cpp:2:
In file included from
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/10.2.0/../../../../include/c++/10.2.0/bitset:1595:
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/10.2.0/../../../../include/c++/10.2.0/debug/bitset:356:26:
error: use of overloaded operator '==' is ambiguous (with operand types 'const
std::__debug::bitset<3>::_Base' (aka 'const bitset<3UL>') and 'const
bitset<3UL>' (aka 'const std::__debug::bitset<3>'))
{ return _M_base() == __rhs; }
~~~~~~~~~ ^ ~~~~~
foo.cpp:5:16: note: in instantiation of member function
'std::__debug::bitset<3>::operator==' requested here
bool test = (a == b);
^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/10.2.0/../../../../include/c++/10.2.0/bitset:1306:7:
note: candidate function
operator==(const bitset<_Nb>& __rhs) const _GLIBCXX_NOEXCEPT
^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/10.2.0/../../../../include/c++/10.2.0/debug/bitset:355:7:
note: candidate function (with reversed parameter order)
operator==(const bitset<_Nb>& __rhs) const _GLIBCXX_NOEXCEPT
^
1 error generated
```
g++ does not, but I guess this still warrants checking ?
