[Pkg-gnupg-maint] Bug#643341: libgpg-error-dev: cross-compiling anything based on libgpg-error is painful

[Colin Watson]

On Wed, Sep 03, 2014 at 06:34:29PM +0200, Helmut Grohne wrote:
> On Tue, Sep 27, 2011 at 01:15:27PM +0100, Colin Watson wrote:
> > libgpg-error-dev ships its own gpg-error-config program which dependent
> > packages are supposed to use.  Unfortunately this doesn't play
> > particularly well with standard cross-build setups; nothing knows that
> > per-architecture versions of gpg-error-config need to be installed in
> > some kind of per-architecture path, so if you try to cross-build
> > anything that build-depends on libgpg-error-dev (such as libgcrypt11) it
> > fails because it tries to link against libgpg-error libraries for the
> > architecture you're building on rather than the architecture you're
> > building for.
> 
> I have problems reproducing this issue in rebootstrap[1].  Since
> libgpg-error-dev is M-A:no, a cross builder will just pull in the host
> version of libgpg-error-dev.  This actually works out quite well,
> because gpg-error-config is a shell script and thus executable for the
> build architecture.  Of course, this means that trying to use it in a
> native compile will result in garbage.  Still crossing reverse build
> dependencies of libgpg-error-dev such as libgcrypt11 or libgcrypt20 just
> work in my experience.  Their configure scripts first check for
> <triplet>-gpg-error-config, which is not found, and then fall back to
> gpg-error-config, which works. So are you talking about cross building
> in a packaging context (where I do not see a problem) or about cross
> building for users (where there currently is no packaged toolchain)?

I filed this report before multiarch cross-building was a thing, so it
was more complicated to arrange to use the host architecture version.
>From that point of view I expect it is indeed less of a problem
nowadays.

That said, the problem hasn't gone away entirely as we'll encounter it
as soon as we have something like a package that needs to build both
build and host architecture versions of a package linked against
libgpg-error.

-- 
Colin Watson                                       [cjwatson at debian.org]