Re: [PATCH 2/2] Let package manager override CFLAGS and CPPFLAGS

[Eric Biggers <ebiggers@kernel.org>]

On Wed, May 20, 2020 at 04:08:11PM -0400, Jes Sorensen wrote:
> From: Jes Sorensen <jsorensen@fb.com>
> 
> Package managers such as RPM wants to build everything with their
> preferred flags, and we shouldn't hard override flags.
> 
> Signed-off-by: Jes Sorensen <jsorensen@fb.com>
> ---
>  Makefile | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/Makefile b/Makefile
> index e7fb5cf..7bcd5e4 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -32,15 +32,14 @@ cc-option = $(shell if $(CC) $(1) -c -x c /dev/null -o /dev/null &>/dev/null; \
>  #### Common compiler flags.  You can add additional flags by defining CFLAGS
>  #### and/or CPPFLAGS in the environment or on the 'make' command line.

The above comment is still being made outdated.  IMO, just remove it.

>  
> -override CFLAGS := -O2 -Wall -Wundef				\
> +CFLAGS := -O2 -Wall -Wundef				\
>  	$(call cc-option,-Wdeclaration-after-statement)		\
>  	$(call cc-option,-Wmissing-prototypes)			\
>  	$(call cc-option,-Wstrict-prototypes)			\
>  	$(call cc-option,-Wvla)					\
> -	$(call cc-option,-Wimplicit-fallthrough)		\
> -	$(CFLAGS)
> +	$(call cc-option,-Wimplicit-fallthrough)
>  
> -override CPPFLAGS := -D_FILE_OFFSET_BITS=64 $(CPPFLAGS)
> +CPPFLAGS := -D_FILE_OFFSET_BITS=64 $(CPPFLAGS)

On the other thread you ageed that CPPFLAGS should be left as-is, but here you
removed 'override'.  I think always using -D_FILE_OFFSET_BITS=64 is what we
want, since it avoids incorrect builds on 32-bit platforms.  Right?

- Eric