[Bug c/79055] gcc should not warn about the assignment-allocation character 'm' of scanf when POSIX is enabled

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79055

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2017-02-10
                 CC|                            |msebor at gcc dot gnu.org
     Ever confirmed|0                           |1

--- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> ---
I agree that complaining about POSIX isn't very useful when targeting a POSIX
environment but I'm not sure expecting -Wpedantic/-pedantic not to warn POSIX
extensions to ISO C is in supported by the documented purpose of the options:

    Issue all the warnings demanded by strict ISO C and ISO C++; reject all
programs that use forbidden extensions, and some other programs that do not
follow ISO C and ISO C++. For ISO C, follows the version of the ISO C standard
specified by any -std option used.

I wonder if this could be somehow handled either by adding a new -std=posixXX
option or extending the existing -std=gnuXX options to extend to some version
of POSIX.

I'll confirm this as a reasonable request.  It seems that there would be other
uses for a strict POSIX-conformance mode besides the %m scanf directive (e.g.,
GCC could warn on POSIX obsolescent/deprecated features).