Re: toolchain/51955: incorrect varargs warning

[David Holland <dholland-bugs%netbsd.org@localhost>]

The following reply was made to PR toolchain/51955; it has been noted by GNATS.

From: David Holland <dholland-bugs%netbsd.org@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: toolchain/51955: incorrect varargs warning
Date: Tue, 14 Mar 2017 07:43:42 +0000

 On Sat, Feb 11, 2017 at 03:40:01PM +0000, Martin Husemann wrote:
  >  Looking at the preprocessor output (which does not differ for std=gnu++14
  >  vs. std=gnu++11), our headers generate:
  >  
  >  	__builtin_va_start(( ap ), ( fmt ))
  >  
  >  while it would work w/o the extra paranthesises:
  >  
  >  	__builtin_va_start( ap , fmt )
  >  
  >  Language lawyers?
 
 It's a gcc-defined construct so it's up to them to decide what works;
 that said, it seems strange that extra parens would break it and I'd
 certainly call it gcc's bug.
 
  >  I have reported it upstream:
  >  
  >  	https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79466
 
 The upstream report contains a reference to a commit that reportedly
 makes it go away, if anyone wants to tinker.
 
 -- 
 David A. Holland
 dholland%netbsd.org@localhost