Re: Getting Apple's libstdc++ debug mode into the FSF tree

[Benjamin Kosnik <bkoz at redhat dot com>]

>5) g++specs to deal with -lstdc++-debug: this will be a small patch 
>that teaches the driver to deal with the debug library. This is the 
>only change to the compiler that will be absolutely required.

This is fine for the time being. 

Long-term, the thought elegantly expressed when --enable-debug went in
is that maybe a -debug=c,c++ flag would link in the correct debug
libraries automatically, much the way -pthread operates. Thus, on linux

g++ -debug foo.cc

would link in

/usr/lib/debug/libc
(prefix)/lib/debug/libstdc++

Anyway. Would be nice, huh?

However, because the configure/build issues for debug target libraries
have not been standardized, this seems unlikely in the near term, and
your approach seems ok. I still like the lib/debug/libstdc++ bits
better, but since we can't do the above, it doesn't really matter.

>10) Better error message reporting: we'll see the use of this 
>error-reporting mechanism, but they'll be hidden from the compiler with 
>preprocessor macros. This patch will flip the switch to use a different 
>error-reporting mechanism that gives much more information about errors 
>found by the debug mode.

I'm interested in this, but suppose I might as well just wait to see
your patch.

>One question before I finish: would it help if I created one big 
>ball-o-wax patch now, in advance of the smaller patches, so that those 
>daring enough can try the whole of the debug mode first? It may help 
>when reviewing the smaller patches, although I believe the structure of 
>the above plan will give the same effect.

To tell you the truth, I'd like to see this patch first, and reserve the
right to suggest implementing it all in one bite.

I suspect the patch is huge. Thus, the best solution would be to put it
up on an apple web site, and pass the URL to this list. I suggest
putting it up as a compressed patch, and then also putting up a full
libstdc++-v3 source directory with the patch applied that people can
just download.

If you run into problems with this, let me know, and I can put it up for
you on my people.redhat.com page.

best,
benjamin