Re: [patch RFC] cpp macro surgery

[Benjamin Kosnik <bkoz at redhat dot com>]

> 1)  Style cleanups as per C++STYLE items.  Very few of these.  (Wrong
> indentation, chunks of blank lines, nothing killer.)

Sooooo nice.

> 2)  More comments in c++config as to what macro has what effect.

Great.

> 3)  Most importantly, lots of cpp macro cleanup all through the headers;
> this also cleans out lots of macros definitions in c++config.  The generic
> SGI STL is just chock full of stuff like
> 
>     #if we have partial ordering of template functions
>     do cool things
>     #else
>     kludge around it
>     #endif
> 
> and
> 
>     #if ! (we're using GCC 2.7 or SGI 5.3 or (some compiler from the
>            beginning of the Epoch))
>     standard-conforming code
>     #endif
> 
> There's no sense in having cpplib do the exact same tests over and over and
> always coming up with the same known results.  So conditionally compiled
> code that /never/ happens is removed with this patch, 'prox 160KB worth.
> 
> This also replaces backwards-combatible macros like
> 
>     #define __STD_QUALIFIER std::
> 
> with their values directly; there's no way the current code could be
> compiled without namespaces, so there's no point in supporting hooks
> to disable them, etc.  Likewise for templates, certain keywords, etc.
> Makes the code much easier to read.

Fantastic. Were you able to time compilation speeds with the pruned 
headers? Is there any noticable difference?

>     - things dealing with the two SGI STL pthread headers; those are
>       hideous and I don't feel like dealing with them right now, also
>       they aren't used much

I've been avoiding this work too. Thread consistency is a libstdc++, gcc, 
libjava issue that is going to have to be done sanely by everybody.

> All the files that I touched that already had an FSF copyright had 2001
> added to the year (most already had it).

Ok.

> For changes like __STD::foo -> std::foo, naturally the whole line is
> included twice in the diff, so the patch is about 300K and needed zipping.

Wow. Ok, well can you post a URL to the patch? That might be the way to 
go. Or post the gzipped patch. 

I'm really interested in the timing difference. (Just a ball park, it 
took the 'make check' routines x with and y  without would be fine.)

thanks again for doing this.
-benjamin