klibc - Jun 2012 - [PATCH] klibc: introduce EXTRA_KLIBCWARNFLAGS variable

From: Maciej ?enczykowski <maze at google.com>

Introduce new EXTRA_KLIBCWARNFLAGS variable which is appended to
the compiler warning flags.

This can be used to enable compiler warning promotion with:
  make EXTRA_KLIBCWARNFLAGS=-Werror
(and/or to disable individual warnings)

Signed-off-by: Maciej ?enczykowski <maze at google.com>
---
 scripts/Kbuild.klibc |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/scripts/Kbuild.klibc b/scripts/Kbuild.klibc
index f500d5358ef6..e913c5c9a4a9 100644
--- a/scripts/Kbuild.klibc
+++ b/scripts/Kbuild.klibc
@@ -70,7 +70,8 @@ KLIBCREQFLAGS     := $(call cc-option, -fno-stack-protector, )
\
                      $(call cc-option, -fwrapv, )
 KLIBCARCHREQFLAGS : KLIBCOPTFLAGS     :-KLIBCWARNFLAGS    := -W -Wall
-Wno-sign-compare -Wno-unused-parameter
+KLIBCWARNFLAGS    := -W -Wall -Wno-sign-compare -Wno-unused-parameter \
+        $(EXTRA_KLIBCWARNFLAGS)
 KLIBCSHAREDFLAGS  : KLIBCBITSIZE      : KLIBCLDFLAGS      :-- 
1.7.9.4

On Wed, 27 Jun 2012, Maciej ?enczykowski wrote:
> From: Maciej ?enczykowski <maze at google.com>
> 
> Introduce new EXTRA_KLIBCWARNFLAGS variable which is appended to
> the compiler warning flags.
> 
> This can be used to enable compiler warning promotion with:
>   make EXTRA_KLIBCWARNFLAGS=-Werror
> (and/or to disable individual warnings)
> 
> Signed-off-by: Maciej ?enczykowski <maze at google.com>
> ---
>  scripts/Kbuild.klibc |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
Looks good to me, waiting on Sam to eyeball and ack/nack it?
 
> diff --git a/scripts/Kbuild.klibc b/scripts/Kbuild.klibc
> index f500d5358ef6..e913c5c9a4a9 100644
> --- a/scripts/Kbuild.klibc
> +++ b/scripts/Kbuild.klibc
> @@ -70,7 +70,8 @@ KLIBCREQFLAGS     := $(call cc-option,
-fno-stack-protector, ) \
>                       $(call cc-option, -fwrapv, )
>  KLIBCARCHREQFLAGS :>  KLIBCOPTFLAGS     :> -KLIBCWARNFLAGS    := -W
-Wall -Wno-sign-compare -Wno-unused-parameter
> +KLIBCWARNFLAGS    := -W -Wall -Wno-sign-compare -Wno-unused-parameter \
> +        $(EXTRA_KLIBCWARNFLAGS)
>  KLIBCSHAREDFLAGS  :>  KLIBCBITSIZE      :>  KLIBCLDFLAGS      :>
--
> 1.7.9.4
> 
> _______________________________________________
> klibc mailing list
> klibc at zytor.com
> http://www.zytor.com/mailman/listinfo/klibc
-- 
maks

On Thu, Jun 28, 2012 at 05:30:42PM +0200, maximilian attems
wrote:
> On Wed, 27 Jun 2012, Maciej ?enczykowski wrote:
> 
> > From: Maciej ?enczykowski <maze at google.com>
> > 
> > Introduce new EXTRA_KLIBCWARNFLAGS variable which is appended to
> > the compiler warning flags.
> > 
> > This can be used to enable compiler warning promotion with:
> >   make EXTRA_KLIBCWARNFLAGS=-Werror
> > (and/or to disable individual warnings)
> > 
> > Signed-off-by: Maciej ?enczykowski <maze at google.com>
> > ---
> >  scripts/Kbuild.klibc |    3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> Looks good to me, waiting on Sam to eyeball and ack/nack it?
The kbuild way to deal with this on a directory base is to use:

    ccflags-y := -Werror

IMO this approach is better because:
1) We can pass any options to cc - we are not restricted to warning related
options
2) lower-case signals that this is not globel - but local for this directory
3) The "-y" part allows you to say ccflags-$(CONFIG_FOO) := -DFOO
4) It is aligned with kbuild

I am obviously a bit biased here as I do not see much other build systems
than kbuild....

	Sam

Awesome, but how do you pass that in from the command line?
or are you talking about a purely hypothetical scenario?

On Thu, Jun 28, 2012 at 10:07 AM, Sam Ravnborg <sam at ravnborg.org>
wrote:
> On Thu, Jun 28, 2012 at 05:30:42PM +0200, maximilian attems wrote:
>> On Wed, 27 Jun 2012, Maciej ?enczykowski wrote:
>>
>> > From: Maciej ?enczykowski <maze at google.com>
>> >
>> > Introduce new EXTRA_KLIBCWARNFLAGS variable which is appended to
>> > the compiler warning flags.
>> >
>> > This can be used to enable compiler warning promotion with:
>> > ? make EXTRA_KLIBCWARNFLAGS=-Werror
>> > (and/or to disable individual warnings)
>> >
>> > Signed-off-by: Maciej ?enczykowski <maze at google.com>
>> > ---
>> > ?scripts/Kbuild.klibc | ? ?3 ++-
>> > ?1 file changed, 2 insertions(+), 1 deletion(-)
>>
>> Looks good to me, waiting on Sam to eyeball and ack/nack it?
>
> The kbuild way to deal with this on a directory base is to use:
>
> ? ?ccflags-y := -Werror
>
> IMO this approach is better because:
> 1) We can pass any options to cc - we are not restricted to warning related
options
> 2) lower-case signals that this is not globel - but local for this
directory
> 3) The "-y" part allows you to say ccflags-$(CONFIG_FOO) := -DFOO
> 4) It is aligned with kbuild
>
> I am obviously a bit biased here as I do not see much other build systems
> than kbuild....
>
> ? ? ? ?Sam
>


-- 
Maciej A. ?enczykowski
Kernel Networking Developer @ Google
1600 Amphitheatre Parkway, Mountain View, CA 94043
tel: +1 (650) 253-0062

On Thu, Jun 28, 2012 at 12:23:45PM -0700, Maciej ?enczykowski
wrote:
> Awesome, but how do you pass that in from the command line?
> or are you talking about a purely hypothetical scenario?
As this was in kbuild.klibc I assumed this was for use
in kbuild files.
Also in kbuild EXTRA_... is for use in kbuild files.

For the command-line in kbuild KCFLAGS=... is used.
Again - keeping in sync with kernel kbuild would be good.

	Sam

On Thu, Jun 28, 2012 at 09:35:13PM +0200, Sam Ravnborg
wrote:
> On Thu, Jun 28, 2012 at 12:23:45PM -0700, Maciej ?enczykowski wrote:
> > Awesome, but how do you pass that in from the command line?
> > or are you talking about a purely hypothetical scenario?
> 
> As this was in kbuild.klibc I assumed this was for use
> in kbuild files.
> Also in kbuild EXTRA_... is for use in kbuild files.
> 
> For the command-line in kbuild KCFLAGS=... is used.
> Again - keeping in sync with kernel kbuild would be good.
Care to respin based on the feedback?

thanks.

-- 
maks