This is the mail archive of the cygwin-apps mailing list for the Cygwin project.

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: 64bit: cygstdc++-6.dll

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

           ^           ^

It's hard to see, but the error message actually does have double underscores.

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:;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.


P.S. I'll be offline until Thursday.

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]