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Re: perl-5.14.4

On Feb  9 19:49, Corinna Vinschen wrote:
> On Feb  9 18:15, Achim Gratz wrote:
> > Corinna Vinschen writes:
> > > I think it's important to keep the information in sync while building
> > > the packages.  A later rebase will break the connection between debug
> > > symbols and runtime symbols as well, obviously.
> > 
> > Obviously?  I have no indication that the debug information is damaged
> > once it's been stripped off into a separate file.  Which may be a hint
> > on what rebase might do wrong.
> What I mean is this.  If the debug info file does not refer to the
> same addresses than the file in memory, then GDB doesn't resolve the
> symbols correctly.
> > > Maybe we should think of rebasing the actual binaries as well as their
> > > debugging counterparts to keep everything in sync, but that's a bit
> > > much effort...
> > 
> > I may not understand what is really going on, but the way I see it,
> > rebase does exactly that while the debug information is still part of
> > the object file.  It seems to do something extra or wrong, since objcopy
> > will the not be able to copy out that information.  Looking with objdump
> > reveals the section is still there ans has contents, but it doesn't get
> > associated with the code in the correct manner anymore.
> I'm not an expert on this stuff either, so I can just assume that the
> rebasing doesn't catch the debug info and that the debug info then
> points into nirvana.  I also don't know if there's a way around that.

Also, is it possible that we have relocation types in the file which
are not handled by rebase?  I just had a quick look into the sources
and there's a type IMAGE_REL_BASED_ABSOLUTE which is skipped.  Or,
what if e.g. the expression

  *patch_adr += difference;

in imagehelper/ is mistreated because of a missing gcc
-fwrapv option on the command line?

There might be quite a few problems lurking here...


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Maintainer                 cygwin AT cygwin DOT com
Red Hat

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