--- file_not_specified_in_diff +++ file_not_specified_in_diff @@ -, +, @@ --- make.conf.example +++ make.conf.example @@ -22,6 +22,15 @@ # Example: #USE="X gtk gnome -alsa" +# Host Setting +# =========== +# +# All RV64 systems should use this host setting: +CHOST="riscv64-unknown-linux-gnu" + +# whereas all RV32 ones should use: +#CHOST="riscv-unknown-linux-gnu" + # Host and optimization settings # ============================== # @@ -39,9 +48,31 @@ # -frecord-gcc-switches, since otherwise the check could result in false # positive results. # -# Please refer to the GCC manual for a list of possible values. +# -mcpu= tells the compiler to take full advantage of the ABI and +# instructions available on a certain CPU. This will produce code which may +# not run on other RISC-V CPUs, even if they support the same ISA. +# +# -mtune= results in code optimised for a specific CPU +# (e.g. SiFive U74) or family (e.g. the SiFive 7 series) without breaking +# compatibility with other RISC-V CPUs supporting the same ISA. +# +# -march= specifies the exact ISA for which to generate code. +# This is normally not needed if you set -mcpu but might be useful for CPUs +# not explicitly supported by gcc yet. Should that be the case and you aren't +# sure what ISA string to use, the output of /proc/cpuinfo might give you a hint. +# +# -mabi= specifies the integer and floating-point calling convention +# to use. Again, this is normally not needed if you set -mcpu. Care should be +# taken while setting both -march and -mabi, as some calling conventions are +# impossible to implement on some ISAs. +# +# Please refer to the section "RISC-V Options" of the GCC manual for a list +# of possible ABI, architecture, CPU and feature values. +# +# Decent examples: # -#CFLAGS="-O2 -pipe" +#CFLAGS="-mcpu=sifive-u74 -O2 -pipe" +#CFLAGS="-mtune=sifive-7-series -O2 -pipe" # # If you set a CFLAGS above, then this line will set your default C++ flags to # the same settings. @@ -76,7 +107,7 @@ # DO NOT PUT ANYTHING BUT YOUR SPECIFIC ~ARCHITECTURE IN THE LIST. # IF YOU ARE UNSURE OF YOUR ARCH, OR THE IMPLICATIONS, DO NOT MODIFY THIS. # -#ACCEPT_KEYWORDS="~arch" +#ACCEPT_KEYWORDS="~riscv" # ACCEPT_LICENSE is used to mask packages based on licensing restrictions. # It may contain both license and group names, where group names are