Hi Nicholas I made the changes below to debian/rules in Ubuntu. I'm not sure if it makes sense to apply them in Debian (yet), but here they are for reference.
export DEB_BUILD_MAINT_OPTIONS = hardening=+all +export DEB_CFLAGS_MAINT_STRIP = -march=x86-64-v3 +export DEB_CXXFLAGS_MAINT_STRIP = -march=x86-64-v3 +export DEB_LDFLAGS_MAINT_STRIP = -march=x86-64-v3 I think it is fine to do this unconditionally, we don't want -march=x86-64-v3 on any architecture. > If there's a future way to detect an x86-64-v3 build, I think the > sensible fix here is to raise the baseline SIMD choice to match. In Ubuntu's amd64v3 implementation, DEB_HOST_ARCH remains amd64, and DEB_HOST_ARCH_VARIANT is set to amd64v3. ifeq (,$(findstring cpuopt,$(DEB_BUILD_OPTIONS))) ifeq ($(DEB_HOST_ARCH), amd64) +ifeq ($(DEB_HOST_ARCH_VARIANT), amd64v3) + COMMON_CONFIG_PARAMS += -DGMX_SIMD=AVX2_256 +else COMMON_CONFIG_PARAMS += -DGMX_SIMD=SSE4.1 +endif else ifeq ($(DEB_HOST_ARCH), arm64) COMMON_CONFIG_PARAMS += -DGMX_SIMD=ARM_NEON_ASIMD else I set GMX_SIMD=AVX2_256 based on the suggestion in LP: #2131605 [1]. Regards Graham [1] https://bugs.launchpad.net/ubuntu/+source/gromacs/+bug/2131605
