[sane-devel] [PATCH] undef linux before defining STRINGIFY

[Olaf Meeuwissen]

Niels Ole Salscheider writes:

> Am 2015-06-09 14:21, schrieb m. allan noah:
>> We need more info here. Where do you see this expansion problem?
>> 
>> allan
>
> The problem is that LIBDIR is passed as a define from the build system.
> Then, STRINGIFY(LIBDIR) is used in backend/dll.c to get a string of the 
> search path for the backends.
> This seems to be fine but it can become a problem since "linux" is 
> definded to "1" by default.
>
> This causes an issue on e. g. Exherbo, my linux distribution. Exherbo 
> installs all packages to /usr/target-triplet/{bin,lib,include,...} so 
> that you can have packages for different architectures on the same root. 
> On my system, sane would be installed to /usr/x86_64-pc-linux-gnu/..., 
> so that LIBDIR would be defined to be /usr/x86_64-pc-linux-gnu/lib.
> But now, STRINGIFY(LIBDIR) turns this into /usr/x86_64-pc-1-gnu/lib 
> (since it also expands linux) - and as a result, sane cannot find any 
> backends.

Rather than willy-nilly undefine `linux` (unconditionally at that) in
include/sane/sanei.h without really knowing what else might break ;-),
I would remove the `STRINGIFY()` calls from backend/dll.c.  The build
system passes LIBDIR as a properly quoted string already with a

 -DLIBDIR="$(libdir)/sane"

in AM_CPPFLAGS in backend/Makefile.am.

Hope this helps,
-- 
Olaf Meeuwissen, LPIC-2           FLOSS Engineer -- AVASYS CORPORATION
FSF Associate Member #1962               Help support software freedom
                 http://www.fsf.org/jf?referrer=1962