[Bug c++/67776] New: Missing warning when using asm labels

[gccbugzilla at limegreensocks dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67776

            Bug ID: 67776
           Summary: Missing warning when using asm labels
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gccbugzilla at limegreensocks dot com
  Target Milestone: ---

When compiling this code:

void f(void)
{
   int foo asm("myfoo") = 42;
}

using: gcc -c sta7.c

I (correctly) get the warning message: 

   warning: ignoring asm-specifier for non-static local variable 'foo'

However, if I rename the file from sta7.c to sta7.cpp, I no longer get the
warning.  Since the variable is still a non-static local variable, I expected
to still get the warning.

While not particularly interesting of itself, this makes me wonder what other c
error checking might be getting skipped in c++.