Re: [v3] concept check macros, excess-errors

[Phil Edwards <pedwards at disaster dot jaj dot com>]

[list moved from gcc-pcatches to libstdc++]

On Tue, Apr 17, 2001 at 06:03:30PM -0700, Benjamin Kosnik wrote:
>    Now, _GLIBCPP_CONCEPT_CHECKS means the concept checking code will
>    be exercised. Having it undefined means it's not active. This

Works for me.

> Phil if you'd like to write configure bits to turn on/off the macro
> (and have it off by default), I think this is a good idea.

This was easy, but one thing remains before checkin:

>    In addition, concept checking code in the Makefiles (!) was
>    removed. 
[...]
> *** 306,312 ****
>   # the concept-checking symbols.  So we must disable the checks while
>   # actually building the library.
>   AM_CXXFLAGS = \
> ! 	-fno-implicit-templates -D_GLIBCPP_NO_CONCEPT_CHECKS \
>   	$(LIBSUPCXX_CXXFLAGS) \
>   	$(WARN_CXXFLAGS) \
>   	$(OPTIMIZE_CXXFLAGS) \
> --- 306,312 ----
>   # the concept-checking symbols.  So we must disable the checks while
>   # actually building the library.
>   AM_CXXFLAGS = \
> ! 	-fno-implicit-templates \
>   	$(LIBSUPCXX_CXXFLAGS) \
>   	$(WARN_CXXFLAGS) \
>   	$(OPTIMIZE_CXXFLAGS) \

...when the user configures with --enable-concept-checks, we still need a
way to turn them off while building the library itself.  I have no problem
with not doing this in the makefiles, but we should decide on how.

Maybe the enabling macro test in concept_check.h should be augmented with
something like system.h's IN_GCC macro, signifying that we're not yet in
user-land but still building ourselves.  We haven't needed such a thing yet,
and it'd be nice to keep going without one.

Or put a -D back in the makefile and change the test to

  #if !defined(_GLIBCPP_CONCEPT_CHECKS)
      || defined (NO_WAY_IN_HELL_DO_WE_WANT_THESE_ON_RIGHT_NOW)
  ...empty defines...

Or etc, etc.  Opinions solicited; choose yer poison.  :-)


Phil

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