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 >