CMAKE - NVHCP fail on SVE builds

[antoine-morvan]

Hello,

I was building OpenBLAS 0.3.29 on a Grace CPU (neoverse V2) using the latest NVHPC tolchain (25.1).

I use the CMake build system, allong with the following flags & variables :

export CC=nvc
export CXX=nvc++
export FC=nvfortran

export ARCH_FLAGS="-tp=host"
export OPT_FLAGS="-O3"

export CFLAGS="${ARCH_FLAGS} ${OPT_FLAGS}"
export CXXFLAGS="${ARCH_FLAGS} ${OPT_FLAGS}"
export FCFLAGS="${ARCH_FLAGS} ${OPT_FLAGS}"
export FFLAGS="$FCFLAGS"
export F90LAGS="$FCFLAGS"
cmake \
    -Wno-dev \
    -G "Unix Makefiles" \
    -DCMAKE_BUILD_TYPE=Release \
    -DBUILD_SHARED_LIBS=ON \
    -DBUILD_STATIC_LIBS=ON \
    -DBUILD_BENCHMARKS=ON \
    -DDYNAMIC_ARCH=OFF \
    -DUSE_THREAD=ON -DUSE_OPENMP=ON \
    -DTARGET=ARMV8SVE \
    $OPENBLAS_DIR

CMake generates a Makefile, but at some point it fails during lapack build :

[ 23%] Building C object CMakeFiles/LAPACKE.dir/lapack-netlib/LAPACKE/src/lapacke_sbbcsd.c.o
$SYS_ROOT/Linux/rhel-9.4/aarch64/compilers/nvhpc/24.5/prefix/Linux_aarch64/24.5/compilers/bin/nvc  -I$HOME/test/nvhpc_openblas_repro/OpenBLAS-0.3.29/lapack-netlib/LAPACKE/include -tp=host -O3  -DHAVE_C11 -mp -DUSE_OPENMP -tp px -march=armv8-a+sve -fPIC -DGEMM_GEMV_FORWARD -DSMALL_MATRIX_OPT -DSMP_SERVER -DNO_WARMUP -DMAX_CPU_NUMBER=288 -DMAX_PARALLEL_NUMBER=1 -DMAX_STACK_ALLOC=2048 -DNO_AFFINITY -DVERSION="\"0.3.29\"" -DBUILD_SINGLE -DBUILD_DOUBLE -DBUILD_COMPLEX -DBUILD_COMPLEX16 -fast -O3 -DNDEBUG  -DHAVE_LAPACK_CONFIG_H -MD -MT CMakeFiles/LAPACKE.dir/lapack-netlib/LAPACKE/src/lapacke_sbbcsd.c.o -MF CMakeFiles/LAPACKE.dir/lapack-netlib/LAPACKE/src/lapacke_sbbcsd.c.o.d -o CMakeFiles/LAPACKE.dir/lapack-netlib/LAPACKE/src/lapacke_sbbcsd.c.o -c $HOME/test/nvhpc_openblas_repro/OpenBLAS-0.3.29/lapack-netlib/LAPACKE/src/lapacke_sbbcsd.c
nvc-Error-Switch -tp with unknown keyword armv8-a+sve
-tp=host|native|neoverse-n1|neoverse-v1|neoverse-v2
                    Select target processor
    host            Link native version of HPC SDK cpu math library
    native          Alias for -tp host
    neoverse-n1     Arm Neoverse N1 architecture
    neoverse-v1     Arm Neoverse V1 architecture (SVE x 256)
    neoverse-v2     Arm Neoverse V2 architecture (SVE x 128)
make[2]: *** [CMakeFiles/LAPACKE.dir/build.make:76: CMakeFiles/LAPACKE.dir/lapack-netlib/LAPACKE/src/lapacke_sbbcsd.c.o] Error 1

I suspect the arch for this compiler is not set properly.

I understand that the cmake builds are still experimental, just here to report the issue to improve support :)

Best.

[martin-frbg]

Seems like nvhpc support had fallen behind a bit (again), hopefully fixed by #5140 now