Bug#1087831: openal-soft: FTBFS on powerpc|ppc64: assumes that PowerPC machines, toolchains support Altivec

Source: openal-soft
Version: 1.24.0-1
Severity: normal
Tags: upstream
Justification: fails to build from source on non-release architectures
X-Debbugs-Cc: [email protected]
User: [email protected]
Usertags: powerpc ppc64

https://buildd.debian.org/status/fetch.php?pkg=openal-soft&arch=powerpc&ver=1%3A1.24.0-1&stamp=1731961701&raw=0
> In file included from /<<PKGBUILDDIR>>/common/pffft.cpp:102:
> /usr/lib/gcc/powerpc-linux-gnu/14/include/altivec.h:34:2: error: #error Use the "-maltivec" flag to enable PowerPC AltiVec support
>    34 | #error Use the "-maltivec" flag to enable PowerPC AltiVec support
>       |  ^~~~~
> /<<PKGBUILDDIR>>/common/pffft.cpp:103:14: error: ‘__vector’ does not name a type; did you mean ‘vector’?
>   103 | using v4sf = vector float;
>       |              ^~~~~~
> /<<PKGBUILDDIR>>/common/pffft.cpp:105:14: error: ‘v4sf’ does not name a type
>   105 | force_inline v4sf vzero() noexcept { return (vector float)vec_splat_u8(0); }
>       |              ^~~~

https://buildd.debian.org/status/fetch.php?pkg=openal-soft&arch=ppc64&ver=1%3A1.24.0-1&stamp=1731960486&raw=0
shows similar symptoms on ppc64.

This could probably be worked around by building with -DPFFFT_SIMD_DISABLE
on the two affected architectures.

I am not interested in powerpc myself (my only powerpc machine is older
than some active Debian contributors, and has been packed up for donation
to a computing history museum) but I'm reporting this bug because it occurs
to me that it would be easy to work around #1087828 and this bug with a
single change, something like this (untested!):

ifneq ($(filter powerpc% ppc%,$(DEB_HOST_ARCH_CPU)),)
export DEB_CPPFLAGS_MAINT_APPEND += -DPFFFT_SIMD_DISABLE
endif

It would be useful if a PowerPC porter could verify this and turn it
into a tested patch.

    smcv