[Buildroot] Why is libbsd limited to ARM, x86 and x86_64?

[Arnout Vandecappelle <arnout@mind.be>]

On 02-02-16 16:30, Carlos Santos wrote:
> Hello,
> 
> I'm working on a project for PowerPC in which libbsd would be useful. However the package is restricted to ARM, x86 and x86_64 architectures, since Config.in contains this:
> 
>   # libbsd requires a.out.h, which is only available for those
>   # architectures: arm, x86 (and alpha, currently not supported in Buildroot;
>   # also m68k which is currently not enabled, so can't be tested.)
>   default y if BR2_arm || BR2_i386 || BR2_x86_64
> 
> However, my PowerPC toolchain, generated by crosstool-NG, provides the required a.out.h file. It is based on GCC 4.8.2, GLIBC 2.19 and Kernel 3.10.47.
> 
> Where does the information about the missing a.out.h on PowerPC comes from?

 I had to do some archeology for this one :-)

 This exclusion was from the time that we only supported glibc for external
toolchains and it didn't get too much attention. So we missed the fact that
glibc doesn't include linux/a.out.h so you won't get this[1] error. And it also
seems that libbsd doesn't really require a.out support in the architecture (PPC
doesn't support a.out), it just needs the a.out.h file to be present (in uClibc,
a.out.h includes linux/a.out.h; in glibc, it doesn't). So for glibc, it works on
any architecture.

 Sometime later, the bump to 0.6.0 made libbsd require a glibc toolchain [2].
But of course, nobody noticed that this meant that the architecture dependencies
are no longer needed.

 So it would be great if you could prepare a patch that removes the arch
dependency and test if libbsd builds on all the arches that have glibc: aarch64,
mips, sh, microblaze, sparc, nios2.

 Regards,
 Arnout
 [1]
http://autobuild.buildroot.org/results/019/019091312ec547520370ffad967b53e23f54a14b/
[2]
http://autobuild.buildroot.net/results/e94/e949d8fabeeecc74bd1c324c516e0b4938c99dbc/




-- 
Arnout Vandecappelle                          arnout at mind be
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