(printf) ("hello world\n");

[mec dot gnu at mindspring dot com (Michael Elizabeth Chastain)]

I have a language lawyer question.

  int main ()
  {
    (printf) ("hello world\n");
    return 0;
  }

Is this a conforming C program?

There is no "#include <stdio.h>" so there is no declaration
in scope for printf.

gcc 2.95.3 and gcc 3.3.2 both say:

  hello.c: In function `main':
  hello.c:3: `printf' undeclared (first use in this function)
  hello.c:3: (Each undeclared identifier is reported only once
  hello.c:3: for each function it appears in.)

This happens with each of:

  -std=iso9899:1990
  -std=iso9899:199409
  -std=iso9899:1999

But the HP ansi-c and aCC compilers accept it just fine.

This kind of code comes out of a macro expansion with readline 4.3
and gcc 3.3.2 on native hppa2.0w-hp-hpux11.11.  It's the end
result of an interaction between multibyte support in hpux11
and a strange-looking workaround in readline.

Of course the question "is this conforming ..." depends on a particular
standard.  So I think I am asking three questions, one for each of the
three standards.

If the program is not conforming, then I can work on a patch for
readline.  But if the program is conforming, then I can file a PR
against gcc (and I'll still have to patch readline).

(Personally I would be happier if this program is not conforming.)

Michael C