Message-ID: <0ab801c306bf$4dacb430$0600000a@broadpark.no>
From: "Gisle Vanem" <giva AT bgnett DOT no>
To: "djgpp" <djgpp AT delorie DOT com>
Subject: __builtin_va_list bug?
Date: Sun, 20 Apr 2003 00:02:00 +0200
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Reply-To: djgpp AT delorie DOT com

I'm porting some code from Watcom to gcc/djgpp and encountered
tons of warnings on illegal use of va_arg(). So I cooked up a little 
test:

#include <stdarg.h>
char x;
void foo (va_list arg)
{
  x = va_arg (arg, char);
}

This gives a warning "`char' is promoted to `int' when passed through `...'"
Fair enough, but when I produce an asm-listing, here's what I get:
        .file   "test.c"
        .section .text
.globl _foo
_foo:
        pushl   %ebp
        movl    %esp, %ebp
        int     $5
.comm _x,16
        .ident  "GCC: (GNU) 3.2.2"

What's the "int $5" doing there?
Is this a gcc bug or feature? If so, is there a fix?
Using "va_arg (arg,int)" produces the correct code.

As you see, I'm using gcc 3.2.2.

--gv