Re: [boost] [Wiki] Changes in information about gcc warnings.

Subject: Re: [boost] [Wiki] Changes in information about gcc warnings.
From: Stephan T. Lavavej (stl_at_[hidden])
Date: 2011-01-12 20:42:43

[Paul A. Bristow]
> I'm only reporting what it says in
> http://msdn.microsoft.com/en-us/library/2c8f766e%28v=VS.100%29.aspx
> "The compiler only supports up to 56 #pragma warning statements in a
> compiland."
> I'm not *quite* sure what that means either (or why even?).

I asked Tanveer Gani, our compiler front-end dev lead, and he said that this is simply incorrect: "Maybe "10^" got accidentally deleted? :-) I can't imagine why there'd be a limit for the number of #pragma warnings and the warning state stack uses linked nodes, not a static array."

My own experiments have also encountered no such limit. I've filed a bug (DevDiv#122565) telling our doc team to remove this sentence.

> But I suspect it explains why this method of warning suppression doesn't
> always work.

#pragma warning has surprising interactions with templates, and certain codegen warnings must be applied at the level of functions instead of individual statements, but push/disable/pop by itself shouldn't have problems.

Stephan T. Lavavej
Visual C++ Libraries Developer