[Bug c++/103583] New: Range loop: "error: 'begin' was not declared in this scope" when 'end' is missing

[shlomo at fastmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103583

            Bug ID: 103583
           Summary: Range loop: "error: 'begin' was not declared in this
                    scope" when 'end' is missing
           Product: gcc
           Version: 11.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: shlomo at fastmail dot com
  Target Milestone: ---

Compiling the following with gcc -c:

struct A {
    int *begin();
    // int *end();
};
void foo(A a) {
    for (auto it : a) { }
}

shows two error messages:

error: ‘begin’ was not declared in this scope
error: ‘end’ was not declared in this scope

The first error message is incorrect.
If only one of 'begin' and 'end' is missing, GCC shouldn't print an error about
the other one.