RF: Set -std=c++14 for nvcc-compiled code - CUDA 11.0 is the earliest to

support c++17

config/buildSettings.mk

@@ -65,7 +65,7 @@ ARCHLIBS =
 #    armadillo structures may have different byte-alignment
 #    to equivalent g++-compiled structures (see
 #    include/armadillo_bits/compiler_setup.hpp)
-ARCHNVCCFLAGS = -DARMA_ALLOW_FAKE_GCC
+ARCHNVCCFLAGS = -DARMA_ALLOW_FAKE_GCC -std=c++14
 
 # Linker flags for CUDA projects.
 ARCHNVCCLDFLAGS =

config/vars.mk

@@ -119,11 +119,16 @@ CXXFLAGS    += ${CPPFLAGS} ${ARCHCXXFLAGS} ${USRCXXFLAGS} ${INCFLAGS}
 LDFLAGS     += ${ARCHLDFLAGS} ${USRLDFLAGS}   \
                -L. -L${DEVLIBDIR} -L${LIBDIR} \
                 ${LIBS} ${ARCHLIBS}
-NVCCFLAGS   += --compiler-options "${CPPFLAGS}"     \
-               ${ARCHNVCCFLAGS}                     \
-               --compiler-options "${ARCHCXXFLAGS}" \
-               ${USRNVCCFLAGS}                      \
-               --compiler-options "${USRCXXFLAGS}"  \
+# Remove any -std=c++ options, as we are already setting
+# -std in ARCHNVCCFLAGS (seee buildSettings.mk), and
+# passing another one via --compiler-options will confuse
+# nvcc. We assume that project Makefile has not added
+# -std to USRCXXFLAGGS/USRCPPFLAGS.
+NVCCFLAGS   += --compiler-options "${CPPFLAGS}"                            \
+               ${ARCHNVCCFLAGS}                                            \
+               --compiler-options "$(patsubst -std=c++%,,${ARCHCXXFLAGS})" \
+               ${USRNVCCFLAGS}                                             \
+               --compiler-options "${USRCXXFLAGS}"                         \
                ${INCFLAGS}
 NVCCLDFLAGS += ${ARCHNVCCLDFLAGS}                  \
                --compiler-options "${ARCHLDFLAGS}" \