[Opencxx-users] Re: [opencxx] Another question regarding double inheritance

[Grzegorz J. <ja...@he...>]

Hi,

Which version of OpenC++ does it?

Regards
Grzegorz

On 1 Nov 2002, Francois Taiani wrote:

> Hi again,
>
> I'm applying OpenC++ on a program with namespaces and double
> inheritance, and occ seems to have troubles when it encounters the
> following pattern: (which compile correctly with "g++ -c".)
> --
> class A{};
> namespace N
> {
>   class B { };
>   class A : virtual public ::A, virtual public B
>   {};
> }
> --
> If I launch occ on this bit of code (here for instance with the default
> metaclass Class), I get a segmentation fault:
> --
> $ /usr/bin/occ -E -SClass test2.cc
> zsh: segmentation fault  /usr/bin/occ -SClass test2.cc
> --
> I've used gdb to investigate what was going on and it seems occ is
> trapped in an infinite recursion. Below is what the bottom of the stack
> looks like just after the segfault. Environment::SearchBaseOrUsing ()
> and Environment::LookupType() recursively call each other until the
> memory space available to the stack gets exhausted.
> ---
> <--snip-- Infinite recursion leading to segmentation fault-->
> ..
> #32640 0x08069434 in Environment::SearchBaseOrUsing ()
> #32641 0x080693c9 in Environment::LookupType ()
> #32642 0x08069434 in Environment::SearchBaseOrUsing ()
> #32643 0x080693c9 in Environment::LookupType ()
> #32644 0x08069434 in Environment::SearchBaseOrUsing ()
> #32645 0x080693c9 in Environment::LookupType ()
> #32646 0x08069434 in Environment::SearchBaseOrUsing ()
> #32647 0x080693c9 in Environment::LookupType ()
> #32648 0x080692bb in Environment::LookupClassMetaobject ()
> #32649 0x0806af6f in Walker::RecordBaseclassEnv ()
> #32650 0x08085764 in ClassWalker::RecordMembers ()
> #32651 0x08085245 in ClassWalker::TranslateClassSpec ()
> #32652 0x0806c799 in Walker::TranslateClassSpec ()
> #32653 0x08062904 in PtreeClassSpec::Translate ()
> #32654 0x0806b014 in Walker::Translate ()
> #32655 0x0806d72d in Walker::TranslateTypespecifier ()
> #32656 0x0806b8d3 in Walker::TranslateDeclaration ()
> #32657 0x08062440 in PtreeDeclaration::Translate ()
> #32658 0x0806b014 in Walker::Translate ()
> #32659 0x0806c3a8 in Walker::TranslateBrace ()
> #32660 0x08062244 in PtreeBrace::Translate ()
> #32661 0x0806b014 in Walker::Translate ()
> #32662 0x0806b765 in Walker::TranslateNamespaceSpec ()
> #32663 0x08062394 in PtreeNamespaceSpec::Translate ()
> #32664 0x0806b014 in Walker::Translate ()
> #32665 0x0805de0a in Compile ()
> #32666 0x0805db2a in Compile ()
> #32667 0x0805d941 in Compile ()
> #32668 0x0805d834 in Compile ()
> #32669 0x0805d7b4 in main ()
> #32670 0x400ca0bf in __libc_start_main () from /lib/libc.so.6
> ---
> Interstingly, the segfault disappears if I remove any of the base
> classes of N::A. For instance occ works fine on
> --
> class A{};
>
> namespace N
> {
>   class B { };
>   class A : virtual public ::A // , virtual public B
>   {};
> }
> --
> The problem also disappears if I use another name for N::A (one that
> does not mask ::A). I think this is a bug, but I'm not sure. Would
> someone have any comment on it ?
>
> Thanks in advance
>
> Francois
>
> --
> Francois Taiani                 +33 (0) 5 6133 6406
> LAAS-CNRS (http://www.laas.fr)  Dependable Computing
> http://www.laas.fr/~ftaiani     and Fault Tolerance
>
>
>

##################################################################
# Grzegorz Jakacki                       Huada Electronic Design #
# Senior Engineer, CAD Dept.              1 Gaojiayuan, Chaoyang #
# tel. +86-10-64365577 x2074               Beijing 100015, China #
# Copyright (C) 2002 Grzegorz Jakacki, HED. All Rights Reserved. #
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