Re: [PATCH v5 1/4] mk: introduce helper to check valid compiler argument

["Phil Yang (Arm Technology China)" <Phil.Yang@arm.com>]

> -----Original Message-----
> From: Jerin Jacob Kollanukkaran <jerinj@marvell.com>
> Sent: Monday, February 25, 2019 2:11 AM
> To: thomas@monjalon.net
> Cc: dev@dpdk.org; Phil Yang (Arm Technology China) <Phil.Yang@arm.com>;
> bruce.richardson@intel.com; jerinj@marvell.com; Pavan Nikhilesh
> Bhagavatula <pbhagavatula@marvell.com>
> Subject: [dpdk-dev] [PATCH v5 1/4] mk: introduce helper to check valid
> compiler argument
> 
> Introduce rte_cc_has_argument() Makefile helper to check a given argument is
> support by the compiler.
> 
> Example Usage:
> 
> include $(RTE_SDK)/mk/rte.helper.mk
> MACHINE_CFLAGS += $(call rte_cc_has_argument, -mcpu=octeontx2)
> 
> This would allow adding -mcpu=octeontx2 in MACHINE_CFLAGS if it is only
> supported by the compiler. The use case for such scheme is to enable the
> mcpu optimization if the compiler supports else it needs to compile the
> source code without any errors.
> 
> This patch also moves inclusion of toolchain's rte.vars.mk to before the
> machine's rte.vars.mk inclusion to make correct CC available for the cross
> compile case.
> 
> Signed-off-by: Jerin Jacob <jerinj@marvell.com>
> Signed-off-by: Pavan Nikhilesh <pbhagavatula@marvell.com>
> ---
> 
> Change history of this series:
> 
> v2 Changes:
>  - Add meson build support.
> 
> v3 Changes:
>  - Squash meson build support into config support for thunderx2/octeontx2.
> 
> v4 Changes:
>  - Fix incorrect signoff marrvell -> marvell.
> 
> v5 Changes:
>  - Fix incorrect meson flag parsing(Phil Yang)
>  - Squash meson cross build patch(5/5) into configuration update patches for
>  thunderx2(3/5) and octeontx2(4/5)(Thomas)
>  - Changed octeontx2's march as armv8-a and added the extension required
>    instead of armv8-2a(Phil Yang)
>  - Improved rte_cc_has_argument() implementaion by removing the temp
>    file(Thomas)
> 
> ---
>  mk/rte.helper.mk              | 10 ++++++++++
>  mk/target/generic/rte.vars.mk | 22 +++++++++++-----------
>  2 files changed, 21 insertions(+), 11 deletions(-)  create mode 100644
> mk/rte.helper.mk
> 
> diff --git a/mk/rte.helper.mk b/mk/rte.helper.mk new file mode 100644 index
> 000000000..6e7fd03d7
> --- /dev/null
> +++ b/mk/rte.helper.mk
> @@ -0,0 +1,10 @@
> +# SPDX-License-Identifier: BSD-3-Clause # Copyright(c) 2018 Marvell
> +International Ltd
> +
> +# rte_cc_has_argument
> +# Usage: MACHINE_CFLAGS += $(call rte_cc_has_argument, -mno-avx512f) #
> +Return the argument if the argument is supported by the compiler.
> +#
> +define rte_cc_has_argument
> +	$(shell $(CC) -E $(1) -xc /dev/null 1>/dev/null 2>/dev/null && echo
> +$(1)) endef
> diff --git a/mk/target/generic/rte.vars.mk b/mk/target/generic/rte.vars.mk
> index dd149acc9..25a578ad7 100644
> --- a/mk/target/generic/rte.vars.mk
> +++ b/mk/target/generic/rte.vars.mk
> @@ -7,6 +7,17 @@
>  # executive environment.
>  #
> 
> +#
> +# toolchain:
> +#
> +#   - define CC, LD, AR, AS, ...
> +#   - define TOOLCHAIN_CFLAGS variable (overridden by cmdline value)
> +#   - define TOOLCHAIN_LDFLAGS variable (overridden by cmdline value)
> +#   - define TOOLCHAIN_ASFLAGS variable (overridden by cmdline value)
> +#   - may override any previously defined variable
> +#
> +include $(RTE_SDK)/mk/toolchain/$(RTE_TOOLCHAIN)/rte.vars.mk
> +
>  #
>  # machine:
>  #
> @@ -45,17 +56,6 @@ endif
>  #
>  include $(RTE_SDK)/mk/arch/$(RTE_ARCH)/rte.vars.mk
> 
> -#
> -# toolchain:
> -#
> -#   - define CC, LD, AR, AS, ...
> -#   - define TOOLCHAIN_CFLAGS variable (overridden by cmdline value)
> -#   - define TOOLCHAIN_LDFLAGS variable (overridden by cmdline value)
> -#   - define TOOLCHAIN_ASFLAGS variable (overridden by cmdline value)
> -#   - may override any previously defined variable
> -#
> -include $(RTE_SDK)/mk/toolchain/$(RTE_TOOLCHAIN)/rte.vars.mk
> -
>  #
>  # exec-env:
>  #
> --
> 2.20.1

Reviewed-by: Phil Yang <phil.yang@arm.com>
For this patch set.

Thanks,
Phil