Bug#918329: apriltag ftbfs on release architectures

[Matthias Klose <doko@debian.org>]

Control: reassign -1 src:apriltag
Control: tags -1 + moreinfo
thanks

please attach the preprocessed source, it's incomplete as a GCC report.

On 05.01.19 19:59, Adrian Bunk wrote:
> Control: reassign -1 gcc-8
> Control: affects -1 src:apriltag
> 
> On Sat, Jan 05, 2019 at 08:44:32AM +0100, Matthias Klose wrote:
>> Package: src:apriltag
>> Version: 0.10.0-1
>> Severity: serious
>> Tags: sid buster
>>
>> apriltag ftbfs on release architectures, where it built before.  Looks like the
>> build system is exaggerating optimization flags, using -O4 nonsense.
> 
> -O4 is treated as -O3, so that is harmless.
> 
> The actual bug is in gcc, and also present with -O2.
> 
> Compiling a not too complicated C file that assigns different buildtime 
> integer constants to all 65k members of an array is not very fast on amd64
> (this is Coffee Lake at 4.7 GHz):
> 
> $ time gcc -c -O2 tagCircle49h12.c
> 
> real    0m51.891s
> user    0m51.775s
> sys     0m0.116s
> $ 
> 
> 
> But gcc speed on some architectures like ppc64el or arm64 is really pathetic:
> 
> (sid_ppc64el-dchroot)bunk@plummer:~/build/apriltag-0.10.0$ time gcc -c -O2 tagCircle49h12.c
> 
> real    150m38.971s
> user    149m18.332s
> sys     0m57.941s
> (sid_ppc64el-dchroot)bunk@plummer:~/build/apriltag-0.10.0$ 
> 
> (sid_arm64-dchroot)bunk@amdahl:~/build/apriltag-0.10.0$ time gcc -c -O2 tagCircle49h12.c
> 
> real    216m20.266s
> user    215m47.712s
> sys     0m2.172s
> (sid_arm64-dchroot)bunk@amdahl:~/build/apriltag-0.10.0$ 
> 
> 
> cu
> Adrian
>