[Bug c++/128396] New: std::source_location captured by defaulted parameter of await_transform differs between templated coroutine function and normal one

[dr.xiaosa at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=128396

            Bug ID: 128396
           Summary: std::source_location captured by defaulted parameter
                    of await_transform differs between templated coroutine
                    function and normal one
           Product: gcc
           Version: 17.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dr.xiaosa at gmail dot com
  Target Milestone: ---

https://godbolt.org/z/jc13aMb7W

In non-templated coroutine function, a co_await expression calling
await_transform captures std::source_location point to the beginning of its
operand, while the one in a templated coroutine function captures the beginning
of co_await keyword. Clang always captures the beginning of co_await.