Re: [Boost-build] Trivial issues have been neglected.

Subject: Re: [Boost-build] Trivial issues have been neglected.
From: Matthew Chambers (matt.chambers42_at_[hidden])
Date: 2012-10-16 11:09:19

On 10/15/2012 11:29 PM, Steven Watanabe wrote:
> AMDG
>
> On 10/15/2012 07:54 PM, Kohei Takahashi wrote:
>> Hi all,
>>
>> Can anyone handle following two issues?
>>
>> <runtime-debugging>on does nothing for libstdc++...
>> https://svn.boost.org/trac/boost/ticket/4589
>>
>
> This is /not/ a trivial issue.  It may
> be easy to do, but:
> a) _GLIBCXX_DEBUG was broken last time I tried it
>     a few years ago.  It won't work with all versions
>     of gcc.

I've used it with 4.1.2 and it helped a lot to track down some mysterious failures.

> b) Anything the changes the ABI of the compiled
>     libraries needs careful consideration and must
>     be documented.  The libraries that are built need
>     to be ABI compatible with code that isn't compiled
>     using Boost.Build.

Is it really that important that debug builds be ABI compatible between disparate builds? I think 
it's reasonable to EXPECT trouble when linking a debug build to precompiled libraries. That is 
certainly the case on Windows.

> c) <runtime-debugging>on is part of <variant>debug,
>     but I don't think _GLIBCXX_DEBUG is a standard
>     part of debug builds with gcc.
What is a "standard" debug build with gcc? Most people would probably say -g and -O0 but that 
doesn't provide any real debugging support.

I agree it's not trivial, but having a no-op runtime-debugging feature is cringe-worthy. It's as 
good as admitting that GCC (or rather, libstdc++) doesn't provide any "official" runtime debugging 
support which is unfair.

In the spirit of upcoming elections, count this as a vote for turning on _GLIBCXX_DEBUG. :)

Thanks,
-Matt