[C++-sig] boost::python with virtual inheritance and g++ c++0x/11 (testcase attached)

[Jonas Wielicki]

On 05/14/2012 01:33 PM, Niall Douglas wrote:
> Most distros bundle multiple versions of gcc due to this exact 
> problem with frequent bugs. Debian, at least, usually has the 
> previous version and for many years also had the latest from the 3.x 
> and indeed 2.x series.
Well, Fedora doesn't. They only ship a 3.4 series compiler as an
alternative (maybe to build qt3 apps or something?). But actually I like
-std=C++0x, you know.

> Simply have your build chain wire in a non-default compiler by 
> excluding from a list of known broken gcc's. It's what my build 
> system does.
Hm. How did you implement that? I mean, does the build chain build its
own gcc if neccessary and install it to a well-defined path in the
user's home directory?

> On 14 May 2012 at 12:53, Jonas Wielicki wrote:
>> Do you recommend to
>> submit a bug report to the gcc folks on that one?
> 
> I personally do. But getting a bug accepted by gcc isn't easy. You 
> may need to be prepared for them to be a bit caustic to you.
I guessed so. Have to remind the discussion between linux kernel folks
and gcc people over whether its a bug in the gcc when a null pointer
derefenciation in the kernel opens a security hole ;).

> A very small testcase is easiest. They don't like testcases bringing 
> in external libraries such as boost one bit. So be prepared to be 
> aggressive if needs be.
Hm. I'm afraid that this bug is not easy to separate in a small
testcase, because if it was evident, the fedora folks would've (a) filed
a bug at the gcc or (b) put in a patch themselves but definetly (c) not
shipped that compiler.

>>> Also, try Clang. Clang seems to generate better 
>>> debug info for templates anyway.
>> I'll have a look, thanks.
Clang doesn't compile boost python 1.49 at all. Sadly.

I guess I'll have to temporarily build a 4.6 gcc for myself, until that
issue is fixed.

-- 
Jonas