[Bug c++/71003] __extension__ silences pedwarn for "\e" in C but not in C++

[egallager at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71003

--- Comment #2 from Eric Gallager <egallager at gcc dot gnu.org> ---
(In reply to Martin Sebor from comment #1)
> Confirmed.  The manual says clearly that it should work so this is a G++ bug.
> 
> '-Wpedantic' does not cause warning messages for use of the alternate
> keywords
> whose names begin and end with '__'.  Pedantic warnings are also disabled in
> the expression that follows __extension__.

Thanks for confirming.