Re: [libstdc++ PATCH] libstdc++ debug mode

[Doug Gregor <dgregor at apple dot com>]

On Tuesday, July 15, 2003, at 2:57AM, Benjamin Kosnik wrote:
> > 	4) If running the libstdc++ testsuite, add the flag 
> > "-D_GLIBCXX_DEBUG"
> > into the flags returned from --build_cxx in the script
> > libstdc++-v3/scripts/testsuite_flags.
>
> For 4, You should just change
>
> libstdc++-v3/testsuite/libstdc++-v3.dg/dg.exp
> DEFAULT_CXXFLAGS "-DDEBUG_ASSERT"
>
> to
>
> DEFAULT_CXXFLAGS "-D_GLIBCXX_DEBUG"

I changed it in scripts/testsuite_flags because that's a non-permanent 
change that one wouldn't accidentally check in. We really would like to 
run the testsuite twice, once for debug mode and once for release mode, 
but there's no machinery to do that (yet?).

> and in /libstdc++-v3/testsuite/testsuite_hooks.h change
>
> the define of
>
> DEBUG_ASSERT
>
> to
>
> _GLIBCXX_DEBUG

You mean the "#ifdef DEBUG_ASSERT"? That seems unrelated to the debug 
mode...

> Eh. For the time being, please just put the __is_null_pointer bits into
> the string includes.

Okay.

> > 	* include/bits/debug/support.h: New.
> > 	* include/bits/debug/vector.h: New.
> > 	* include/ext/debug/bitset: New.
> > 	* include/ext/debug/deque: New.
>
> Please don't nest directories in here.
>
>          * include/debug: Add your stuff here.

Just to be clear about the purpose of the two separate directories:
	- bits/debug contains the debug-mode wrappers and support code. So 
when you compile with -D_GLIBCXX_DEBUG, an include of <list> will pick 
up bits/debug/list.h and make it std::list.

	- ext/debug contains the debugging wrappers for debug or release mode, 
e.g., including <ext/debug/list> gets you __gnu_cxx::debug::list.

I can put everything into include/debug (files for containers from 
bits/debug will get the prefix "dbg_") but it may be more confusing 
this way.

One last comment on this: at Boost we generally try to match the 
directory structure with the namespace structure, so that, e.g., 
including <outer/inner/foo> gets you outer::inner::foo. If we move all 
of the debug code into include/debug, then including <debug/list> will 
pull in __gnu_cxx::debug::list.

> Also:
>
>  __GLIBCXX_INTERNAL_DEBUG_MAP_H
>
> to
>
>  _GLIBCXX_DEBUG_MAP_H
>
> like the ext directory duplicate headers.

Ok.

> > 	* debug/Makefile.am: New.
>
> There's got to be a better solution than this. . . If you don't want to
> keep the old, hacky src/Makefile.am rules, that is ok with me, but 
> let's
> try to come up with something that's an improvement that doesn't
> duplicate so much of src/Makefile.am in the process. Alexandre Oliva
> recently suggested looking at the multilib approach, which I believe
> libjava uses: can you take a look at that approach please, or quiz him
> to see what he means by this?

I'll look into multilibs.

	Doug