[Bug c++/86602] New: need to check for a placeholder in argument to noexcept

[zhonghao at pku dot org.cn]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86602

            Bug ID: 86602
           Summary: need to check for a placeholder in argument to
                    noexcept
           Product: gcc
           Version: 9.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zhonghao at pku dot org.cn
  Target Milestone: ---

g++ accepts this invalid code:

void f();
void f(int);
bool b = noexcept(f);

[over.over]p1: "An overloaded function name shall not be used without arguments
in contexts other than those listed."

clang++ rejects it:

code1.cpp:3:19: error: reference to overloaded function could not be resolved;
      did you mean to call it with no arguments?
bool b = noexcept(f);
                  ^
                   ()
code1.cpp:2:6: note: possible target for call
void f(int);
     ^
code1.cpp:1:6: note: possible target for call
void f();
     ^
1 error generated.