Does not build with -march=x86-64-v3

[tillea]

Hi,
I'd like to forward this bug report to the Debian bug tracking system:

Starting with LLVM 12 and GCC 11 GCC introduces optimizations for new micro-architecture levels from the x86-64 psABI. I verified workbench is building with the current level (x86-64), but not with x86-64-v3.

Could you please have a look into this problem?

Kind regards, Andreas.

[coalsont]

/usr/bin/ld: ../kloewe/dot/libdot.a(dot.c.o): in function `dot_set_impl':
dot.c:(.text+0x17a): undefined reference to `sdot_avx'
/usr/bin/ld: dot.c:(.text+0x18b): undefined reference to `ddot_avx'
/usr/bin/ld: dot.c:(.text+0x19c): undefined reference to `dsdot_avx'
/usr/bin/ld: dot.c:(.text+0x1ba): undefined reference to `sdot_avx512'
/usr/bin/ld: dot.c:(.text+0x1cb): undefined reference to `ddot_avx512'
/usr/bin/ld: dot.c:(.text+0x1dc): undefined reference to `dsdot_avx512'

The SIMD dot product library has ifdef guards because it only works on x86_64, presumably the build system checks and source #ifdefs aren't in agreement on how to identify "x86-64-v3". As a quick fix, set cmake boolean variable WORKBENCH_USE_SIMD to false to disable it.