Re: [PATCH 1/2] kbuild: refactor scripts/Makefile.extrawarn
On Wed, Aug 28, 2019 at 11:19 PM Sedat Dilek wrote:
>
> On Wed, Aug 28, 2019 at 9:20 AM Sedat Dilek wrote:
> >
> > On Wed, Aug 28, 2019 at 7:55 AM Masahiro Yamada
> > wrote:
> > >
> > > Instead of the warning-[123] magic, let's accumulate compiler options
> > > to KBUILD_CFLAGS directly as the top Makefile does. I think this makes
> > > easier to understand what is going on in this file.
> > >
> > > This commit slightly changes the behavior, I think all of which are OK.
> > >
> > > [1] Currently, cc-option calls are needlessly evaluated. For example,
> > > warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
> > > needs evaluating only when W=3, but it is actually evaluated for
> > > W=1, W=2 as well. With this commit, only relevant cc-option calls
> > > will be evaluated. This is a slight optimization.
> > >
> > > [2] Currently, unsupported level like W=4 is checked by:
> > > $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
> > > This will no longer be checked, but I do not think it is a big
> > > deal.
> > >
> >
> > Hi Masahiro Yamada,
> >
> > thanks for your patch series.
> >
> > If KBUILD_ENABLE_EXTRA_GCC_CHECKS does extra(-warning)-checks for GCC and
> > Clang,
> > please rename the Kconfig into...
You repeatedly mentioned "Kconfig" in your posts,
where there is nothing related to Kconfig.
> >
> > KBUILD_ENABLE_EXTRA_CC_CHECKS
You missed the fact this is already used
not only for C compilers, but also for Device Tree compiler.
(see scripts/Makefile.lib)
One more thing, this is the environment variable
that Kbuild officially supports.
Keeping the backward compatibility is must.
When I mentioned to rename this before,
Arnd suggested to keep it as is.
https://patchwork.kernel.org/patch/10172331/#21385013
I do not know whether he is still planning that rework, though.
> > ...or something similiar (and maybe with some notes in its Kconfig
> > help-text?).
What did you mean by "Kconfig help-text" ?
> >
>
> I have tested both patches against recent kbuild-next and can boot on
> bare metal with clang.
>
> I have *not* passed any W= to my make, but I see that clang's W=1
> kbuild-cflags are active.
>
> [ scripts/Makefile.extrawarn ]
>
> ifeq ("$(origin W)", "command line")
> export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
> endif
>
> #
> # W=1 - warnings that may be relevant and does not occur too often
> #
> ifneq ($(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
> [ ... ]
> KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN1
>
> else
>
> # W=1 also stops suppressing some warnings
>
> ifdef CONFIG_CC_IS_CLANG
> KBUILD_CFLAGS += -Wno-initializer-overrides
> KBUILD_CFLAGS += -Wno-format
> KBUILD_CFLAGS += -Wno-sign-compare
> KBUILD_CFLAGS += -Wno-format-zero-length
> endif # CONFIG_CC_IS_CLANG
>
> endif # KBUILD_ENABLE_EXTRA_GCC_CHECKS
>
> These clang KBUILD_CFLAGS are active independently of passing W=1.
>
> $ grep '\-Wno-initializer-overrides'
> build-log_5.3.0-rc6-2-amd64-cbl-asmgoto.txt | wc -l
> 27195
>
> So the above comment is misleading?
>
> Is W=1 activated by default?
>
> Or do I miss something?
I won't comment back to your long analysis.
Instead, I will post v2.
I hope you will notice something.
> [ Documentation/kbuild/kbuild.rst ]
>
> KBUILD_ENABLE_EXTRA_GCC_CHECKS
> --
> If enabled over the make command line with "W=1", it turns on additional
> gcc -W... options for more extensive build-time checking.
>
> What about?
>
> KBUILD_CC_EXTRA_CHECKS (or KBUILD_EXTRA_CC_CHECKS)
> --
> If enabled over the make command line with "W=...", it turns on additional
> compiler warning options like -Wmissing-declarations for more extensive
> build-time checking. For more details see .
>
> W=1 - warnings that may be relevant and does not occur too often
> W=1 - also stops suppressing some warnings
> W=2 - warnings that occur quite often but may still be relevant
> W=3 - the more obscure warnings, can most likely be ignored
>
> - Sedat -
--
Best Regards
Masahiro Yamada
Re: [PATCH 1/2] kbuild: refactor scripts/Makefile.extrawarn
> So, if it is desired to pass the CLANG extrawarn compiler-options to
> all W=... then I ask myself why the CLANG block is in the W=1 block
> only?
> So if CLANG extrawarn options are independent of any W=... make-option
> then I prefer to put it in a seperate block with an appropriate
> comment.
>
Maybe something like that (on top of the two patches I had sent).
From: Sedat Dilek
Date: Thu, 29 Aug 2019 11:35:21 +0200
Subject: [PATCH 3/3] kbuild: Move extra warnings for Clang
---
Documentation/kbuild/kbuild.rst | 5 +++--
scripts/Makefile.extrawarn | 21 ++---
2 files changed, 13 insertions(+), 13 deletions(-)
diff --git a/Documentation/kbuild/kbuild.rst b/Documentation/kbuild/kbuild.rst
index 3e65d32af875..fa9772ae2367 100644
--- a/Documentation/kbuild/kbuild.rst
+++ b/Documentation/kbuild/kbuild.rst
@@ -245,10 +245,11 @@ KBUILD_EXTRA_CC_CHECKS
--
If enabled over the make command line with "W=...", it turns on additional
compiler warning options like -Wmissing-declarations for more extensive
-build-time checking. For more details see .
+build-time checking.
+Some extra warning options are set for all W=... settings when using Clang.
+For more details see .
W=1 - warnings that may be relevant and does not occur too often
-W=1 - also stops suppressing some warnings
W=2 - warnings that occur quite often but may still be relevant
W=3 - the more obscure warnings, can most likely be ignored
diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index 72677ee9f202..86c0f8ae7e35 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -5,6 +5,16 @@
KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
+#
+# W=... - stops suppressing some warnings when using Clang
+#
+ifdef CONFIG_CC_IS_CLANG
+KBUILD_CFLAGS += -Wno-initializer-overrides
+KBUILD_CFLAGS += -Wno-format
+KBUILD_CFLAGS += -Wno-sign-compare
+KBUILD_CFLAGS += -Wno-format-zero-length
+endif
+
ifeq ("$(origin W)", "command line")
export KBUILD_EXTRA_CC_CHECKS := $(W)
endif
@@ -30,17 +40,6 @@ KBUILD_CFLAGS += -Wno-sign-compare
KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN1
-else
-
-# W=1 - also stops suppressing some warnings
-
-ifdef CONFIG_CC_IS_CLANG
-KBUILD_CFLAGS += -Wno-initializer-overrides
-KBUILD_CFLAGS += -Wno-format
-KBUILD_CFLAGS += -Wno-sign-compare
-KBUILD_CFLAGS += -Wno-format-zero-length
-endif
-
endif
#
--
2.20.1
- Sedat -
Re: [PATCH 1/2] kbuild: refactor scripts/Makefile.extrawarn
On Thu, Aug 29, 2019 at 12:38 AM 'Nick Desaulniers' via Clang Built
Linux wrote:
>
> On Tue, Aug 27, 2019 at 10:54 PM Masahiro Yamada
> wrote:
> >
> > Instead of the warning-[123] magic, let's accumulate compiler options
> > to KBUILD_CFLAGS directly as the top Makefile does. I think this makes
> > easier to understand what is going on in this file.
> >
> > This commit slightly changes the behavior, I think all of which are OK.
> >
> > [1] Currently, cc-option calls are needlessly evaluated. For example,
> > warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
> > needs evaluating only when W=3, but it is actually evaluated for
> > W=1, W=2 as well. With this commit, only relevant cc-option calls
> > will be evaluated. This is a slight optimization.
> >
> > [2] Currently, unsupported level like W=4 is checked by:
> > $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
> > This will no longer be checked, but I do not think it is a big
> > deal.
> >
> > [3] Currently, 4 Clang warnings (Winitializer-overrides, Wformat,
> > Wsign-compare, Wformat-zero-length) are shown by any of W=1, W=2,
> > and W=3. With this commit, they will be warned only by W=1. I
> > think this is a more correct behavior since each warning belongs
> > to only one warning level.
> >
> > Signed-off-by: Masahiro Yamada
> > ---
> >
> > scripts/Makefile.extrawarn | 104 +++--
> > 1 file changed, 53 insertions(+), 51 deletions(-)
> >
> > diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
> > index a74ce2e3c33e..1fa53968e292 100644
> > --- a/scripts/Makefile.extrawarn
> > +++ b/scripts/Makefile.extrawarn
> > @@ -1,14 +1,6 @@
> > # SPDX-License-Identifier: GPL-2.0
> > #
> > ==
> > -#
> > # make W=... settings
> > -#
> > -# W=1 - warnings that may be relevant and does not occur too often
> > -# W=2 - warnings that occur quite often but may still be relevant
> > -# W=3 - the more obscure warnings, can most likely be ignored
> > -#
> > -# $(call cc-option, -W...) handles gcc -W.. options which
> > -# are not supported by all versions of the compiler
> > #
> > ==
> >
> > KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
> > @@ -17,58 +9,68 @@ ifeq ("$(origin W)", "command line")
> >export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
> > endif
> >
> > -ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS
> > -warning- := $(empty)
> > +#
> > +# W=1 - warnings that may be relevant and does not occur too often
> > +#
> > +ifneq ($(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
> >
> > -warning-1 := -Wextra -Wunused -Wno-unused-parameter
> > -warning-1 += -Wmissing-declarations
> > -warning-1 += -Wmissing-format-attribute
> > -warning-1 += -Wmissing-prototypes
> > -warning-1 += -Wold-style-definition
> > -warning-1 += -Wmissing-include-dirs
> > -warning-1 += $(call cc-option, -Wunused-but-set-variable)
> > -warning-1 += $(call cc-option, -Wunused-const-variable)
> > -warning-1 += $(call cc-option, -Wpacked-not-aligned)
> > -warning-1 += $(call cc-option, -Wstringop-truncation)
> > +KBUILD_CFLAGS += -Wextra -Wunused -Wno-unused-parameter
> > +KBUILD_CFLAGS += -Wmissing-declarations
> > +KBUILD_CFLAGS += -Wmissing-format-attribute
> > +KBUILD_CFLAGS += -Wmissing-prototypes
> > +KBUILD_CFLAGS += -Wold-style-definition
> > +KBUILD_CFLAGS += -Wmissing-include-dirs
> > +KBUILD_CFLAGS += $(call cc-option, -Wunused-but-set-variable)
> > +KBUILD_CFLAGS += $(call cc-option, -Wunused-const-variable)
> > +KBUILD_CFLAGS += $(call cc-option, -Wpacked-not-aligned)
> > +KBUILD_CFLAGS += $(call cc-option, -Wstringop-truncation)
> > # The following turn off the warnings enabled by -Wextra
> > -warning-1 += -Wno-missing-field-initializers
> > -warning-1 += -Wno-sign-compare
> > -
> > -warning-2 += -Wcast-align
> > -warning-2 += -Wdisabled-optimization
> > -warning-2 += -Wnested-externs
> > -warning-2 += -Wshadow
> > -warning-2 += $(call cc-option, -Wlogical-op)
> > -warning-2 += -Wmissing-field-initializers
> > -warning-2 += -Wsign-compare
> > -warning-2 += $(call cc-option, -Wmaybe-uninitialized)
> > -warning-2 += $(call cc-option, -Wunused-macros)
> > -
> > -warning-3 := -Wbad-function-cast
> > -warning-3 += -Wcast-qual
> > -warning-3 += -Wconversion
> > -warning-3 += -Wpacked
> > -warning-3 += -Wpadded
> > -warning-3 += -Wpointer-arith
> > -warning-3 += -Wredundant-decls
> > -warning-3 += -Wswitch-default
> > -warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
> > -
> > -warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
> > -warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
> > -warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
> > -
> > -ifeq ("$(strip $(warning))","")
> > -$(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is
Re: [PATCH 1/2] kbuild: refactor scripts/Makefile.extrawarn
On Tue, Aug 27, 2019 at 10:54 PM Masahiro Yamada
wrote:
>
> Instead of the warning-[123] magic, let's accumulate compiler options
> to KBUILD_CFLAGS directly as the top Makefile does. I think this makes
> easier to understand what is going on in this file.
>
> This commit slightly changes the behavior, I think all of which are OK.
>
> [1] Currently, cc-option calls are needlessly evaluated. For example,
> warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
> needs evaluating only when W=3, but it is actually evaluated for
> W=1, W=2 as well. With this commit, only relevant cc-option calls
> will be evaluated. This is a slight optimization.
>
> [2] Currently, unsupported level like W=4 is checked by:
> $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
> This will no longer be checked, but I do not think it is a big
> deal.
>
> [3] Currently, 4 Clang warnings (Winitializer-overrides, Wformat,
> Wsign-compare, Wformat-zero-length) are shown by any of W=1, W=2,
> and W=3. With this commit, they will be warned only by W=1. I
> think this is a more correct behavior since each warning belongs
> to only one warning level.
>
> Signed-off-by: Masahiro Yamada
> ---
>
> scripts/Makefile.extrawarn | 104 +++--
> 1 file changed, 53 insertions(+), 51 deletions(-)
>
> diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
> index a74ce2e3c33e..1fa53968e292 100644
> --- a/scripts/Makefile.extrawarn
> +++ b/scripts/Makefile.extrawarn
> @@ -1,14 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0
> # ==
> -#
> # make W=... settings
> -#
> -# W=1 - warnings that may be relevant and does not occur too often
> -# W=2 - warnings that occur quite often but may still be relevant
> -# W=3 - the more obscure warnings, can most likely be ignored
> -#
> -# $(call cc-option, -W...) handles gcc -W.. options which
> -# are not supported by all versions of the compiler
> # ==
>
> KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
> @@ -17,58 +9,68 @@ ifeq ("$(origin W)", "command line")
>export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
> endif
>
> -ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS
> -warning- := $(empty)
> +#
> +# W=1 - warnings that may be relevant and does not occur too often
> +#
> +ifneq ($(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
>
> -warning-1 := -Wextra -Wunused -Wno-unused-parameter
> -warning-1 += -Wmissing-declarations
> -warning-1 += -Wmissing-format-attribute
> -warning-1 += -Wmissing-prototypes
> -warning-1 += -Wold-style-definition
> -warning-1 += -Wmissing-include-dirs
> -warning-1 += $(call cc-option, -Wunused-but-set-variable)
> -warning-1 += $(call cc-option, -Wunused-const-variable)
> -warning-1 += $(call cc-option, -Wpacked-not-aligned)
> -warning-1 += $(call cc-option, -Wstringop-truncation)
> +KBUILD_CFLAGS += -Wextra -Wunused -Wno-unused-parameter
> +KBUILD_CFLAGS += -Wmissing-declarations
> +KBUILD_CFLAGS += -Wmissing-format-attribute
> +KBUILD_CFLAGS += -Wmissing-prototypes
> +KBUILD_CFLAGS += -Wold-style-definition
> +KBUILD_CFLAGS += -Wmissing-include-dirs
> +KBUILD_CFLAGS += $(call cc-option, -Wunused-but-set-variable)
> +KBUILD_CFLAGS += $(call cc-option, -Wunused-const-variable)
> +KBUILD_CFLAGS += $(call cc-option, -Wpacked-not-aligned)
> +KBUILD_CFLAGS += $(call cc-option, -Wstringop-truncation)
> # The following turn off the warnings enabled by -Wextra
> -warning-1 += -Wno-missing-field-initializers
> -warning-1 += -Wno-sign-compare
> -
> -warning-2 += -Wcast-align
> -warning-2 += -Wdisabled-optimization
> -warning-2 += -Wnested-externs
> -warning-2 += -Wshadow
> -warning-2 += $(call cc-option, -Wlogical-op)
> -warning-2 += -Wmissing-field-initializers
> -warning-2 += -Wsign-compare
> -warning-2 += $(call cc-option, -Wmaybe-uninitialized)
> -warning-2 += $(call cc-option, -Wunused-macros)
> -
> -warning-3 := -Wbad-function-cast
> -warning-3 += -Wcast-qual
> -warning-3 += -Wconversion
> -warning-3 += -Wpacked
> -warning-3 += -Wpadded
> -warning-3 += -Wpointer-arith
> -warning-3 += -Wredundant-decls
> -warning-3 += -Wswitch-default
> -warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
> -
> -warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
> -warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
> -warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
> -
> -ifeq ("$(strip $(warning))","")
> -$(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
> -endif
> +KBUILD_CFLAGS += -Wno-missing-field-initializers
> +KBUILD_CFLAGS += -Wno-sign-compare
>
> -KBUILD_CFLAGS += $(warning)
> else
>
> +# W=1 also stops suppressing some warnings
> +
> ifdef CONFIG_CC_IS_CLANG
> KBUILD_CFLAGS += -Wno-initializer-overrides
> KBUILD_CFLAGS += -Wno-format
> KBUILD_CFLAGS
Re: [PATCH 1/2] kbuild: refactor scripts/Makefile.extrawarn
On Wed, Aug 28, 2019 at 12:20 AM Sedat Dilek wrote: > > On Wed, Aug 28, 2019 at 7:55 AM Masahiro Yamada > wrote: > > > > Instead of the warning-[123] magic, let's accumulate compiler options > > to KBUILD_CFLAGS directly as the top Makefile does. I think this makes > > easier to understand what is going on in this file. > > > > This commit slightly changes the behavior, I think all of which are OK. > > > > [1] Currently, cc-option calls are needlessly evaluated. For example, > > warning-3 += $(call cc-option, -Wpacked-bitfield-compat) > > needs evaluating only when W=3, but it is actually evaluated for > > W=1, W=2 as well. With this commit, only relevant cc-option calls > > will be evaluated. This is a slight optimization. > > > > [2] Currently, unsupported level like W=4 is checked by: > > $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown) > > This will no longer be checked, but I do not think it is a big > > deal. > > > > Hi Masahiro Yamada, > > thanks for your patch series. > > If KBUILD_ENABLE_EXTRA_GCC_CHECKS does extra(-warning)-checks for GCC and > Clang, > please rename the Kconfig into... > > KBUILD_ENABLE_EXTRA_CC_CHECKS > > ...or something similiar (and maybe with some notes in its Kconfig > help-text?). I too would like to see that changed. -- Thanks, ~Nick Desaulniers
Re: [PATCH 1/2] kbuild: refactor scripts/Makefile.extrawarn
On Wed, Aug 28, 2019 at 02:54:24PM +0900, Masahiro Yamada wrote: > Instead of the warning-[123] magic, let's accumulate compiler options > to KBUILD_CFLAGS directly as the top Makefile does. I think this makes > easier to understand what is going on in this file. > > This commit slightly changes the behavior, I think all of which are OK. > > [1] Currently, cc-option calls are needlessly evaluated. For example, > warning-3 += $(call cc-option, -Wpacked-bitfield-compat) > needs evaluating only when W=3, but it is actually evaluated for > W=1, W=2 as well. With this commit, only relevant cc-option calls > will be evaluated. This is a slight optimization. > > [2] Currently, unsupported level like W=4 is checked by: > $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown) > This will no longer be checked, but I do not think it is a big > deal. > > [3] Currently, 4 Clang warnings (Winitializer-overrides, Wformat, > Wsign-compare, Wformat-zero-length) are shown by any of W=1, W=2, > and W=3. With this commit, they will be warned only by W=1. I > think this is a more correct behavior since each warning belongs > to only one warning level. > > Signed-off-by: Masahiro Yamada Reviewed-by: Nathan Chancellor
Re: [PATCH 1/2] kbuild: refactor scripts/Makefile.extrawarn
Something like that...
[PATCH 1/2] kbuild: Improve extrawarn documentation
[PATCH 2/2] kbuild: Rename extrawarn Kconfig to KBUILD_EXTRA_CC_CHECKS
- Sedat -
From 1275ec0f1d31c4ac57b73b318bdc45151d99e8dc Mon Sep 17 00:00:00 2001
From: Sedat Dilek
Date: Wed, 28 Aug 2019 16:27:13 +0200
Subject: [PATCH 1/2] kbuild: Improve extrawarn documentation
---
Documentation/kbuild/kbuild.rst | 10 --
scripts/Makefile.extrawarn | 2 +-
2 files changed, 9 insertions(+), 3 deletions(-)
diff --git a/Documentation/kbuild/kbuild.rst b/Documentation/kbuild/kbuild.rst
index 62f9d86c082c..f0f1c475d7fa 100644
--- a/Documentation/kbuild/kbuild.rst
+++ b/Documentation/kbuild/kbuild.rst
@@ -243,8 +243,14 @@ To get all available archs you can also specify all. E.g.::
KBUILD_ENABLE_EXTRA_GCC_CHECKS
--
-If enabled over the make command line with "W=1", it turns on additional
-gcc -W... options for more extensive build-time checking.
+If enabled over the make command line with "W=...", it turns on additional
+compiler warning options like -Wmissing-declarations for more extensive
+build-time checking. For more details see .
+
+W=1 - warnings that may be relevant and does not occur too often
+W=1 - also stops suppressing some warnings
+W=2 - warnings that occur quite often but may still be relevant
+W=3 - the more obscure warnings, can most likely be ignored
KBUILD_BUILD_TIMESTAMP
--
diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index 3af1770497fd..6770f8da4e6d 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -32,7 +32,7 @@ KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN1
else
-# W=1 also stops suppressing some warnings
+# W=1 - also stops suppressing some warnings
ifdef CONFIG_CC_IS_CLANG
KBUILD_CFLAGS += -Wno-initializer-overrides
--
2.20.1
From b364881f8b2a7aa258dcdbaba8d6bc57b41def0d Mon Sep 17 00:00:00 2001
From: Sedat Dilek
Date: Wed, 28 Aug 2019 16:30:03 +0200
Subject: [PATCH 2/2] kbuild: Rename extrawarn Kconfig to
KBUILD_EXTRA_CC_CHECKS
---
Documentation/kbuild/kbuild.rst | 2 +-
scripts/Makefile.build | 2 +-
scripts/Makefile.extrawarn | 8
scripts/Makefile.lib| 4 ++--
scripts/genksyms/Makefile | 2 +-
5 files changed, 9 insertions(+), 9 deletions(-)
diff --git a/Documentation/kbuild/kbuild.rst b/Documentation/kbuild/kbuild.rst
index f0f1c475d7fa..dcc83d993459 100644
--- a/Documentation/kbuild/kbuild.rst
+++ b/Documentation/kbuild/kbuild.rst
@@ -241,7 +241,7 @@ To get all available archs you can also specify all. E.g.::
$ make ALLSOURCE_ARCHS=all tags
-KBUILD_ENABLE_EXTRA_GCC_CHECKS
+KBUILD_EXTRA_CC_CHECKS
--
If enabled over the make command line with "W=...", it turns on additional
compiler warning options like -Wmissing-declarations for more extensive
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 2a21ca86b720..1de9b9aa 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -85,7 +85,7 @@ else ifeq ($(KBUILD_CHECKSRC),2)
cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $<
endif
-ifneq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),)
+ifneq ($(KBUILD_EXTRA_CC_CHECKS),)
cmd_checkdoc = $(srctree)/scripts/kernel-doc -none $<
endif
diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index 6770f8da4e6d..0ee4a5a88d2c 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -6,13 +6,13 @@
KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
ifeq ("$(origin W)", "command line")
- export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
+ export KBUILD_EXTRA_CC_CHECKS := $(W)
endif
#
# W=1 - warnings that may be relevant and does not occur too often
#
-ifneq ($(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
+ifneq ($(findstring 1, $(KBUILD_EXTRA_CC_CHECKS)),)
KBUILD_CFLAGS += -Wextra -Wunused -Wno-unused-parameter
KBUILD_CFLAGS += -Wmissing-declarations
@@ -46,7 +46,7 @@ endif
#
# W=2 - warnings that occur quite often but may still be relevant
#
-ifneq ($(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
+ifneq ($(findstring 2, $(KBUILD_EXTRA_CC_CHECKS)),)
KBUILD_CFLAGS += -Wcast-align
KBUILD_CFLAGS += -Wdisabled-optimization
@@ -65,7 +65,7 @@ endif
#
# W=3 - the more obscure warnings, can most likely be ignored
#
-ifneq ($(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
+ifneq ($(findstring 3, $(KBUILD_EXTRA_CC_CHECKS)),)
KBUILD_CFLAGS += -Wbad-function-cast
KBUILD_CFLAGS += -Wcast-qual
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 888e5c830646..1f9e38550ce4 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -248,7 +248,7 @@ quiet_cmd_gzip = GZIP$@
DTC ?= $(objtree)/scripts/dtc/dtc
# Disable noisy checks by default
-ifeq ($(findstring 1,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
+ifeq ($(findstring 1,$(KBUILD_EXTRA_CC_CHECKS)),)
DTC_FLAGS += -Wno-unit_address_vs_reg \
Re: [PATCH 1/2] kbuild: refactor scripts/Makefile.extrawarn
> build-time checking. For more details see . Grrr. s/ Documentation/kbuild/kbuild.rst / scripts/Makefile.extrawarn - Sedat -
Re: [PATCH 1/2] kbuild: refactor scripts/Makefile.extrawarn
On Wed, Aug 28, 2019 at 9:20 AM Sedat Dilek wrote:
>
> On Wed, Aug 28, 2019 at 7:55 AM Masahiro Yamada
> wrote:
> >
> > Instead of the warning-[123] magic, let's accumulate compiler options
> > to KBUILD_CFLAGS directly as the top Makefile does. I think this makes
> > easier to understand what is going on in this file.
> >
> > This commit slightly changes the behavior, I think all of which are OK.
> >
> > [1] Currently, cc-option calls are needlessly evaluated. For example,
> > warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
> > needs evaluating only when W=3, but it is actually evaluated for
> > W=1, W=2 as well. With this commit, only relevant cc-option calls
> > will be evaluated. This is a slight optimization.
> >
> > [2] Currently, unsupported level like W=4 is checked by:
> > $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
> > This will no longer be checked, but I do not think it is a big
> > deal.
> >
>
> Hi Masahiro Yamada,
>
> thanks for your patch series.
>
> If KBUILD_ENABLE_EXTRA_GCC_CHECKS does extra(-warning)-checks for GCC and
> Clang,
> please rename the Kconfig into...
>
> KBUILD_ENABLE_EXTRA_CC_CHECKS
>
> ...or something similiar (and maybe with some notes in its Kconfig
> help-text?).
>
I have tested both patches against recent kbuild-next and can boot on
bare metal with clang.
I have *not* passed any W= to my make, but I see that clang's W=1
kbuild-cflags are active.
[ scripts/Makefile.extrawarn ]
ifeq ("$(origin W)", "command line")
export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
endif
#
# W=1 - warnings that may be relevant and does not occur too often
#
ifneq ($(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
[ ... ]
KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN1
else
# W=1 also stops suppressing some warnings
ifdef CONFIG_CC_IS_CLANG
KBUILD_CFLAGS += -Wno-initializer-overrides
KBUILD_CFLAGS += -Wno-format
KBUILD_CFLAGS += -Wno-sign-compare
KBUILD_CFLAGS += -Wno-format-zero-length
endif # CONFIG_CC_IS_CLANG
endif # KBUILD_ENABLE_EXTRA_GCC_CHECKS
These clang KBUILD_CFLAGS are active independently of passing W=1.
$ grep '\-Wno-initializer-overrides'
build-log_5.3.0-rc6-2-amd64-cbl-asmgoto.txt | wc -l
27195
So the above comment is misleading?
Is W=1 activated by default?
Or do I miss something?
[ Documentation/kbuild/kbuild.rst ]
KBUILD_ENABLE_EXTRA_GCC_CHECKS
--
If enabled over the make command line with "W=1", it turns on additional
gcc -W... options for more extensive build-time checking.
What about?
KBUILD_CC_EXTRA_CHECKS (or KBUILD_EXTRA_CC_CHECKS)
--
If enabled over the make command line with "W=...", it turns on additional
compiler warning options like -Wmissing-declarations for more extensive
build-time checking. For more details see .
W=1 - warnings that may be relevant and does not occur too often
W=1 - also stops suppressing some warnings
W=2 - warnings that occur quite often but may still be relevant
W=3 - the more obscure warnings, can most likely be ignored
- Sedat -
Re: [PATCH 1/2] kbuild: refactor scripts/Makefile.extrawarn
On Wed, Aug 28, 2019 at 7:55 AM Masahiro Yamada
wrote:
>
> Instead of the warning-[123] magic, let's accumulate compiler options
> to KBUILD_CFLAGS directly as the top Makefile does. I think this makes
> easier to understand what is going on in this file.
>
> This commit slightly changes the behavior, I think all of which are OK.
>
> [1] Currently, cc-option calls are needlessly evaluated. For example,
> warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
> needs evaluating only when W=3, but it is actually evaluated for
> W=1, W=2 as well. With this commit, only relevant cc-option calls
> will be evaluated. This is a slight optimization.
>
> [2] Currently, unsupported level like W=4 is checked by:
> $(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
> This will no longer be checked, but I do not think it is a big
> deal.
>
Hi Masahiro Yamada,
thanks for your patch series.
If KBUILD_ENABLE_EXTRA_GCC_CHECKS does extra(-warning)-checks for GCC and Clang,
please rename the Kconfig into...
KBUILD_ENABLE_EXTRA_CC_CHECKS
...or something similiar (and maybe with some notes in its Kconfig help-text?).
Regards,
- Sedat -
> [3] Currently, 4 Clang warnings (Winitializer-overrides, Wformat,
> Wsign-compare, Wformat-zero-length) are shown by any of W=1, W=2,
> and W=3. With this commit, they will be warned only by W=1. I
> think this is a more correct behavior since each warning belongs
> to only one warning level.
>
> Signed-off-by: Masahiro Yamada
> ---
>
> scripts/Makefile.extrawarn | 104 +++--
> 1 file changed, 53 insertions(+), 51 deletions(-)
>
> diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
> index a74ce2e3c33e..1fa53968e292 100644
> --- a/scripts/Makefile.extrawarn
> +++ b/scripts/Makefile.extrawarn
> @@ -1,14 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0
> # ==
> -#
> # make W=... settings
> -#
> -# W=1 - warnings that may be relevant and does not occur too often
> -# W=2 - warnings that occur quite often but may still be relevant
> -# W=3 - the more obscure warnings, can most likely be ignored
> -#
> -# $(call cc-option, -W...) handles gcc -W.. options which
> -# are not supported by all versions of the compiler
> # ==
>
> KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
> @@ -17,58 +9,68 @@ ifeq ("$(origin W)", "command line")
>export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
> endif
>
> -ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS
> -warning- := $(empty)
> +#
> +# W=1 - warnings that may be relevant and does not occur too often
> +#
> +ifneq ($(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
>
> -warning-1 := -Wextra -Wunused -Wno-unused-parameter
> -warning-1 += -Wmissing-declarations
> -warning-1 += -Wmissing-format-attribute
> -warning-1 += -Wmissing-prototypes
> -warning-1 += -Wold-style-definition
> -warning-1 += -Wmissing-include-dirs
> -warning-1 += $(call cc-option, -Wunused-but-set-variable)
> -warning-1 += $(call cc-option, -Wunused-const-variable)
> -warning-1 += $(call cc-option, -Wpacked-not-aligned)
> -warning-1 += $(call cc-option, -Wstringop-truncation)
> +KBUILD_CFLAGS += -Wextra -Wunused -Wno-unused-parameter
> +KBUILD_CFLAGS += -Wmissing-declarations
> +KBUILD_CFLAGS += -Wmissing-format-attribute
> +KBUILD_CFLAGS += -Wmissing-prototypes
> +KBUILD_CFLAGS += -Wold-style-definition
> +KBUILD_CFLAGS += -Wmissing-include-dirs
> +KBUILD_CFLAGS += $(call cc-option, -Wunused-but-set-variable)
> +KBUILD_CFLAGS += $(call cc-option, -Wunused-const-variable)
> +KBUILD_CFLAGS += $(call cc-option, -Wpacked-not-aligned)
> +KBUILD_CFLAGS += $(call cc-option, -Wstringop-truncation)
> # The following turn off the warnings enabled by -Wextra
> -warning-1 += -Wno-missing-field-initializers
> -warning-1 += -Wno-sign-compare
> -
> -warning-2 += -Wcast-align
> -warning-2 += -Wdisabled-optimization
> -warning-2 += -Wnested-externs
> -warning-2 += -Wshadow
> -warning-2 += $(call cc-option, -Wlogical-op)
> -warning-2 += -Wmissing-field-initializers
> -warning-2 += -Wsign-compare
> -warning-2 += $(call cc-option, -Wmaybe-uninitialized)
> -warning-2 += $(call cc-option, -Wunused-macros)
> -
> -warning-3 := -Wbad-function-cast
> -warning-3 += -Wcast-qual
> -warning-3 += -Wconversion
> -warning-3 += -Wpacked
> -warning-3 += -Wpadded
> -warning-3 += -Wpointer-arith
> -warning-3 += -Wredundant-decls
> -warning-3 += -Wswitch-default
> -warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
> -
> -warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
> -warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
> -warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
> -
> -ifeq ("$(strip $(warning))","")
> -$(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
> -endif
>
[PATCH 1/2] kbuild: refactor scripts/Makefile.extrawarn
Instead of the warning-[123] magic, let's accumulate compiler options
to KBUILD_CFLAGS directly as the top Makefile does. I think this makes
easier to understand what is going on in this file.
This commit slightly changes the behavior, I think all of which are OK.
[1] Currently, cc-option calls are needlessly evaluated. For example,
warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
needs evaluating only when W=3, but it is actually evaluated for
W=1, W=2 as well. With this commit, only relevant cc-option calls
will be evaluated. This is a slight optimization.
[2] Currently, unsupported level like W=4 is checked by:
$(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
This will no longer be checked, but I do not think it is a big
deal.
[3] Currently, 4 Clang warnings (Winitializer-overrides, Wformat,
Wsign-compare, Wformat-zero-length) are shown by any of W=1, W=2,
and W=3. With this commit, they will be warned only by W=1. I
think this is a more correct behavior since each warning belongs
to only one warning level.
Signed-off-by: Masahiro Yamada
---
scripts/Makefile.extrawarn | 104 +++--
1 file changed, 53 insertions(+), 51 deletions(-)
diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index a74ce2e3c33e..1fa53968e292 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -1,14 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
# ==
-#
# make W=... settings
-#
-# W=1 - warnings that may be relevant and does not occur too often
-# W=2 - warnings that occur quite often but may still be relevant
-# W=3 - the more obscure warnings, can most likely be ignored
-#
-# $(call cc-option, -W...) handles gcc -W.. options which
-# are not supported by all versions of the compiler
# ==
KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
@@ -17,58 +9,68 @@ ifeq ("$(origin W)", "command line")
export KBUILD_ENABLE_EXTRA_GCC_CHECKS := $(W)
endif
-ifdef KBUILD_ENABLE_EXTRA_GCC_CHECKS
-warning- := $(empty)
+#
+# W=1 - warnings that may be relevant and does not occur too often
+#
+ifneq ($(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
-warning-1 := -Wextra -Wunused -Wno-unused-parameter
-warning-1 += -Wmissing-declarations
-warning-1 += -Wmissing-format-attribute
-warning-1 += -Wmissing-prototypes
-warning-1 += -Wold-style-definition
-warning-1 += -Wmissing-include-dirs
-warning-1 += $(call cc-option, -Wunused-but-set-variable)
-warning-1 += $(call cc-option, -Wunused-const-variable)
-warning-1 += $(call cc-option, -Wpacked-not-aligned)
-warning-1 += $(call cc-option, -Wstringop-truncation)
+KBUILD_CFLAGS += -Wextra -Wunused -Wno-unused-parameter
+KBUILD_CFLAGS += -Wmissing-declarations
+KBUILD_CFLAGS += -Wmissing-format-attribute
+KBUILD_CFLAGS += -Wmissing-prototypes
+KBUILD_CFLAGS += -Wold-style-definition
+KBUILD_CFLAGS += -Wmissing-include-dirs
+KBUILD_CFLAGS += $(call cc-option, -Wunused-but-set-variable)
+KBUILD_CFLAGS += $(call cc-option, -Wunused-const-variable)
+KBUILD_CFLAGS += $(call cc-option, -Wpacked-not-aligned)
+KBUILD_CFLAGS += $(call cc-option, -Wstringop-truncation)
# The following turn off the warnings enabled by -Wextra
-warning-1 += -Wno-missing-field-initializers
-warning-1 += -Wno-sign-compare
-
-warning-2 += -Wcast-align
-warning-2 += -Wdisabled-optimization
-warning-2 += -Wnested-externs
-warning-2 += -Wshadow
-warning-2 += $(call cc-option, -Wlogical-op)
-warning-2 += -Wmissing-field-initializers
-warning-2 += -Wsign-compare
-warning-2 += $(call cc-option, -Wmaybe-uninitialized)
-warning-2 += $(call cc-option, -Wunused-macros)
-
-warning-3 := -Wbad-function-cast
-warning-3 += -Wcast-qual
-warning-3 += -Wconversion
-warning-3 += -Wpacked
-warning-3 += -Wpadded
-warning-3 += -Wpointer-arith
-warning-3 += -Wredundant-decls
-warning-3 += -Wswitch-default
-warning-3 += $(call cc-option, -Wpacked-bitfield-compat)
-
-warning := $(warning-$(findstring 1, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
-warning += $(warning-$(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
-warning += $(warning-$(findstring 3, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)))
-
-ifeq ("$(strip $(warning))","")
-$(error W=$(KBUILD_ENABLE_EXTRA_GCC_CHECKS) is unknown)
-endif
+KBUILD_CFLAGS += -Wno-missing-field-initializers
+KBUILD_CFLAGS += -Wno-sign-compare
-KBUILD_CFLAGS += $(warning)
else
+# W=1 also stops suppressing some warnings
+
ifdef CONFIG_CC_IS_CLANG
KBUILD_CFLAGS += -Wno-initializer-overrides
KBUILD_CFLAGS += -Wno-format
KBUILD_CFLAGS += -Wno-sign-compare
KBUILD_CFLAGS += -Wno-format-zero-length
endif
+
+endif
+
+#
+# W=2 - warnings that occur quite often but may still be relevant
+#
+ifneq ($(findstring 2, $(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),)
+
+KBUILD_CFLAGS += -Wcast-align
+KBUILD_CFLAGS +=
