On Mar 24 03:33, Yaakov (Cygwin/X) wrote: > On 2013-03-23 04:50, Corinna Vinschen wrote: > >On Mar 22 19:11, marco atzeri wrote: > >>latest libstdc++6-4.8-20130319-1 > >> > >>has at least a missing entry point from previous dll > >> > >>cmake fails with > >>"_ZTVN10_cxxabiv117_class_type_infoE could not be located" > > > >However, a quick glance into the symbols exported by libstdc++.a > >shows that the above symbol exists, but with additional leading > >underscores: > > > > _ZTVN10__cxxabiv117__class_type_infoE > > ^ ^ > > It's hard to see, but the error message actually does have double > underscores.
I don't quite understand. From what Marco pasted above, it doesn't. > >The x86_64 ABI does not prepends underscores in front of symbols, > >so there has evidently gone something wrong. I checked my the Linux > >cross toolchain and it is also using the symbols with additional > >leading underscores. Off the top of my head I don't see where this > >discrepancy is caused. > > The PE underscore only applies to the very beginning of a symbol, > not to every component of a C++ symbol name. Those double > underscores are straight from libstdc++ code, as they are internal > symbols. > > In any case, the error is a result of adding one of Dave Korn's patches: > > http://cygwin-ports.git.sourceforge.net/git/gitweb.cgi?p=cygwin-ports/gcc;a=blob;f=4.7-libstdc-dllimport.patch;hb=refs/heads/4.8#l29 > > I have omitted that patch in the new 4.8.0-1. Hopefully Dave can > explain the purpose and necessity of that patch, since it would seem > that using (at least that hunk of) it would require rebuilding most > C++ packages in 64bit/release; if it's really necessary, then we > will want to do that sooner rather than later. That I don't quite understand either. If this is only about missing exported symbols and not about the name, how are the already built C++ packages affected? They could be built, so they didn't use this symbols, apparently. I'm slightly confused now... Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Maintainer cygwin AT cygwin DOT com Red Hat
