On 01/20/2016 06:16 AM, Dan HorĂ¡k wrote:
The current distro defaults are (/usr/lib/rpm/redhat/rpmrc)
optflags: ppc64 %{__global_cflags} -m64
optflags: ppc64p7 %{__global_cflags} -m64 -O3 -mcpu=power7 -mtune=power7
optflags: ppc64le %{__global_cflags} -m64 -mcpu=power7 -mtune=power8
The ppc64le case needs to become '-mcpu=power8 -mtune=power8', as Steven
Munroe notes the only official ppc64le support is with POWER8 hardware.
And gcc has its own defaults which can be set during the build.
The Fedora infrastructure is currently using Power8 HW for the main Koji
build system [1] to produce the binary rpms for the distrobution and we
have planned to reuse the previous Power7+ builders for COPR [2] and
Fedora Cloud.
This will mean that COPR cannot build POWER8 enabled binaries, and that
would be a shame for users of newer hardware.
Carlos, Florian, could you please comment on the situation?
At present glibc in fedora rawhide requires POWER8 hardware.
Why? We build optimized variants of the runtime for POWER8 hardware and
need POWER8 hardware to test the resulting binaries (native build).
This means that glibc for fedora rawhide will be unbuildable in COPR
until COPR is upgraded to POWER8 machines.
However, we can change that, as Florian suggets, it's up to the Fedora
Power community to make a decision as to what is needed to best serve the
IBM hardware users.
We currently have the following support in place (from glibc.spec in rawhide):
# 64-bit BE:
# - Power 620 / 970 ISA (default runtime, compatile with POWER4 and newer)
# - Provided for the large number of PowerPC G5 users.
# - IFUNC support provides optimized core routines for POWER6,
# POWER7, and POWER8 transparently (if not using specific runtimes
# below)
# - POWER6 (has power6x symlink to power6, enabled via AT_PLATFORM)
# - Legacy for old systems. Should be deprecated at some point soon.
# - POWER7 (enabled via AT_PLATFORM)
# - Existing deployments.
# - POWER8 (enabled via AT_PLATFORM)
# - Latest generation.
# 64-bit LE:
# - POWER8 LE (default)
# - Latest generation.
Whatever decisions you make, please tell us and we can adjust the library.
Cheers,
Carlos.