Re: [PATCH net-next v3 1/2] tools: ynl: Allow cross-compiling ynl and associated tools

[Bobby Eshleman <bobbyeshleman@gmail.com>]

On Mon, Sep 07, 2026 at 06:14:35PM +0200, Maxime Chevallier (Netdev Foundation) wrote:
> The ynl tool and libraries may be built standalone or through the
> drivers/net/hw selftest machinery. This may target a different arch, so
> we need to take the CROSS_COMPILE variable into account for LLVM and
> gcc.
> 
> Let's include the tools/scripts/Makefile.include that deals with the
> CC/AR resolution.
> 
> Fixup the ynltool CFLAGS handling to use +=, so that we don't override
> the ones set in Makefile.include.
> 
> Makefile.include also sets the Q variable for verbose mode, so we can
> drop it from the ynltool Makefile. This will allow properly selection
> the verbosity of ynltool builds with the V=1 make flag.
> 
> Reviewed-by: Matthieu Baerts (Netdev Foundation) <matttbe@kernel.org>
> Signed-off-by: Maxime Chevallier (Netdev Foundation) <maxime.chevallier@bootlin.com>

Hey Maxime,

It seems that this patch may break some invocations of make:

  # make -C tools/net/ynl/ynltool O=/tmp/o1
  make: Entering directory '/data/users/bobbyeshleman/linux-worktrees/review/tools/net/ynl/ynltool'
  make: *** No rule to make target '/tmp/o1/json_writer.o', needed by '/tmp/o1/ynltool'.  Stop.
  make: Leaving directory '/data/users/bobbyeshleman/linux-worktrees/review/tools/net/ynl/ynltool'

Best,
Bobby

> ---
>  tools/net/ynl/Makefile           | 1 +
>  tools/net/ynl/generated/Makefile | 3 ++-
>  tools/net/ynl/lib/Makefile       | 3 ++-
>  tools/net/ynl/tests/Makefile     | 2 +-
>  tools/net/ynl/ynltool/Makefile   | 6 ++----
>  5 files changed, 8 insertions(+), 7 deletions(-)
> 
> diff --git a/tools/net/ynl/Makefile b/tools/net/ynl/Makefile
> index 3cefe4ed96cb..838c465d65aa 100644
> --- a/tools/net/ynl/Makefile
> +++ b/tools/net/ynl/Makefile
> @@ -1,5 +1,6 @@
>  # SPDX-License-Identifier: GPL-2.0
>  
> +include ../../scripts/Makefile.include
>  include ../../scripts/Makefile.arch
>  
>  INSTALL	?= install
> diff --git a/tools/net/ynl/generated/Makefile b/tools/net/ynl/generated/Makefile
> index ea4128f612d6..5a186349b5a8 100644
> --- a/tools/net/ynl/generated/Makefile
> +++ b/tools/net/ynl/generated/Makefile
> @@ -1,6 +1,7 @@
>  # SPDX-License-Identifier: GPL-2.0
>  
> -CC=gcc
> +include ../../../scripts/Makefile.include
> +
>  CFLAGS += -std=gnu11 -O2 -W -Wall -Wextra -Wno-unused-parameter -Wshadow \
>  	-I../lib/ -idirafter $(UAPI_PATH)
>  ifeq ("$(DEBUG)","1")
> diff --git a/tools/net/ynl/lib/Makefile b/tools/net/ynl/lib/Makefile
> index 9b98c0599600..7b3eae89982f 100644
> --- a/tools/net/ynl/lib/Makefile
> +++ b/tools/net/ynl/lib/Makefile
> @@ -1,6 +1,7 @@
>  # SPDX-License-Identifier: GPL-2.0
>  
> -CC=gcc
> +include ../../../scripts/Makefile.include
> +
>  CFLAGS += -std=gnu11 -O2 -W -Wall -Wextra -Wno-unused-parameter -Wshadow
>  ifeq ("$(DEBUG)","1")
>    CFLAGS += -g -fsanitize=address -fsanitize=leak -static-libasan
> diff --git a/tools/net/ynl/tests/Makefile b/tools/net/ynl/tests/Makefile
> index 40827ca8e579..99ae7dcd6348 100644
> --- a/tools/net/ynl/tests/Makefile
> +++ b/tools/net/ynl/tests/Makefile
> @@ -2,8 +2,8 @@
>  # Makefile for YNL tests
>  
>  include ../Makefile.deps
> +include ../../../scripts/Makefile.include
>  
> -CC=gcc
>  CFLAGS += -std=gnu11 -O2 -W -Wall -Wextra -Wno-unused-parameter -Wshadow \
>  	-I../lib/ -I../generated/ -I../../../testing/selftests/ \
>  	-idirafter $(UAPI_PATH)
> diff --git a/tools/net/ynl/ynltool/Makefile b/tools/net/ynl/ynltool/Makefile
> index 48b0f32050f0..b8c67cdb4fdf 100644
> --- a/tools/net/ynl/ynltool/Makefile
> +++ b/tools/net/ynl/ynltool/Makefile
> @@ -1,12 +1,12 @@
>  # SPDX-License-Identifier: GPL-2.0-only
>  
>  include ../Makefile.deps
> +include ../../../scripts/Makefile.include
>  
>  INSTALL	?= install
>  prefix  ?= /usr
>  
> -CC := gcc
> -CFLAGS := -Wall -Wextra -Werror -O2
> +CFLAGS += -Wall -Wextra -Werror -O2
>  ifeq ("$(DEBUG)","1")
>    CFLAGS += -g -fsanitize=address -fsanitize=leak -static-libasan
>  endif
> @@ -27,8 +27,6 @@ include $(wildcard *.d)
>  
>  all: $(YNLTOOL)
>  
> -Q = @
> -
>  $(YNLTOOL): ../libynl.a $(OBJS)
>  	$(Q)echo -e "\tLINK $@"
>  	$(Q)$(CC) $(CFLAGS) -o $@ $(OBJS) ../libynl.a -lm
> -- 
> 2.55.0
>