Re: __func__ is not a keyword

Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:

Kaz Kylheku <643-408-1753@kylheku.com> writes:
>

On 2025-03-15, Keith Thompson <Keith.S.Thompson+u@gmail.com> wrote:
>

I'm mildly curious how gcc and clang treat "__func__" internally
that leads to this odd behavior.  The obvious way to implement it
would be to internally create a declaration of __func__ on entry
to each function definition, which shouldn't cause the symptom
you're seeing.  But it's not a conformance issue

>
The main reason is this:
>
  "As an extension, at file (or, in C++, namespace scope), __func__
   evaluates to the empty string."

>
But it produces a diagnostic
>
warning: ?__func__? is not defined outside of function scope
>
And in a very quick look through the documentation, I don't see
a way to disable that warning (other than "-w", which disables
all warnings).  Looks like they don't really want you using this
extension.

It seems more likely that they just don't care.  I expect there
has been very little demand for an option specifically to cover
this situation.

By the way, clang has -Wpredefined-identifier-outside-function,
along with the corresponding no- version to turn off the warning.