Consolidation with CDI-PIO (1.8.x)

This is a follow-up on !8 (closed).

.ci/bb/levante-dkrz/test.icon-pio.intel-classic

@@ -9,6 +9,12 @@ top_srcdir=$(cd "${script_dir}/../../.."; pwd)
 . "${script_dir}/utils.sh"
 init_intelclassic202150
 
+# The following compiler flags are used by the respective ICON configure
+# wrapper. They are not set into stone and can be changed if needed. It is just
+# important to keep them the same as in the wrapper.
+CFLAGS='-g -gdwarf-4 -qno-opt-dynamic-align -O3 -ftz'
+FCFLAGS='-g -gdwarf-4 -pc64 -fp-model source -march=native -O2 -assume realloc_lhs -ftz'
+
 # Make sure that the libtool script has a chance to erroneously link to the
 # shared versions of YAXT and PPM:
 for file in \
@@ -92,6 +98,7 @@ test -f "${top_srcdir}/configure" || "${top_srcdir}/autogen.sh"
 --without-grib_api \
 --without-szlib \
 --without-threads \
+AR="${AR}" \
 BUILD_CC= \
 BUILD_CFLAGS= \
 BUILD_CXX= \
@@ -103,12 +110,12 @@ BUILD_LIBS= \
 BUILD_MPI_C_LIB= \
 BUILD_MPI_FC_LIB= \
 CC="${MPICC}" \
-CFLAGS='-no-prec-sqrt -no-prec-div -fast-transcendentals -m64 -march=core-avx2 -mtune=core-avx2 -no-fma -g -gdwarf-4 -ip -pc64 -std=gnu99 -qno-opt-dynamic-align -O2 -ftz' \
+CFLAGS="${CFLAGS}" \
 CPPFLAGS="-I${NETCDF_ROOT}/include -I${ECCODES_ROOT}/include" \
 CXX=no \
 F77=no \
 FC="${MPIFC}" \
-FCFLAGS="-gdwarf-4 -g -pc64 -fp-model source" \
+FCFLAGS="${FCFLAGS}" \
 LDFLAGS="${LDFLAGS} -L${NETCDF_ROOT}/lib -L${ECCODES_ROOT}/lib64" \
 LIBS='-Wl,--as-needed -lnetcdf -leccodes' \
 MPIROOT= \