On Wed, Sep 30, 2020 at 6:12 PM Andrew Lunn <andrew@xxxxxxx> wrote: > > There is a movement to try to make more and more of /drivers W=1 > clean. But it will only stay clean if new warnings are quickly > detected and fixed, ideally by the developer adding the new code. > > To allow subdirectories to sign up to being W=1 clean for a given > definition of W=1, export the current set of additional compile flags > using the symbol KBUILD_CFLAGS_W1_20200930. Subdirectory Makefiles can > then use: > > subdir-ccflags-y := $(KBUILD_CFLAGS_W1_20200930) > > To indicate they want to W=1 warnings as defined on 20200930. > > Additional warnings can be added to the W=1 definition. This will not > affect KBUILD_CFLAGS_W1_20200930 and hence no additional warnings will > start appearing unless W=1 is actually added to the command > line. Developers can then take their time to fix any new W=1 warnings, > and then update to the latest KBUILD_CFLAGS_W1_<DATESTAMP> symbol. I'm not a fan of this approach. Are DATESTAMP configs just going to keep being added? Is it going to complicate isolating the issue from a randconfig build? If we want more things to build warning-free at W=1, then why don't we start moving warnings from W=1 into the default, until this is no W=1 left? That way we're cutting down on the kernel's configuration combinatorial explosion, rather than adding to it? > > Signed-off-by: Andrew Lunn <andrew@xxxxxxx> > --- > scripts/Makefile.extrawarn | 34 ++++++++++++++++++---------------- > 1 file changed, 18 insertions(+), 16 deletions(-) > > diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn > index 95e4cdb94fe9..957dca35ae3e 100644 > --- a/scripts/Makefile.extrawarn > +++ b/scripts/Makefile.extrawarn > @@ -20,24 +20,26 @@ export KBUILD_EXTRA_WARN > # > # W=1 - warnings which may be relevant and do not occur too often > # > -ifneq ($(findstring 1, $(KBUILD_EXTRA_WARN)),) > - > -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) > +KBUILD_CFLAGS_W1_20200930 += -Wextra -Wunused -Wno-unused-parameter > +KBUILD_CFLAGS_W1_20200930 += -Wmissing-declarations > +KBUILD_CFLAGS_W1_20200930 += -Wmissing-format-attribute > +KBUILD_CFLAGS_W1_20200930 += -Wmissing-prototypes > +KBUILD_CFLAGS_W1_20200930 += -Wold-style-definition > +KBUILD_CFLAGS_W1_20200930 += -Wmissing-include-dirs > +KBUILD_CFLAGS_W1_20200930 += $(call cc-option, -Wunused-but-set-variable) > +KBUILD_CFLAGS_W1_20200930 += $(call cc-option, -Wunused-const-variable) > +KBUILD_CFLAGS_W1_20200930 += $(call cc-option, -Wpacked-not-aligned) > +KBUILD_CFLAGS_W1_20200930 += $(call cc-option, -Wstringop-truncation) > # The following turn off the warnings enabled by -Wextra > -KBUILD_CFLAGS += -Wno-missing-field-initializers > -KBUILD_CFLAGS += -Wno-sign-compare > -KBUILD_CFLAGS += -Wno-type-limits > +KBUILD_CFLAGS_W1_20200930 += -Wno-missing-field-initializers > +KBUILD_CFLAGS_W1_20200930 += -Wno-sign-compare > +KBUILD_CFLAGS_W1_20200930 += -Wno-type-limits > + > +export KBUILD_CFLAGS_W1_20200930 > + > +ifneq ($(findstring 1, $(KBUILD_EXTRA_WARN)),) > > -KBUILD_CPPFLAGS += -DKBUILD_EXTRA_WARN1 > +KBUILD_CPPFLAGS += $(KBUILD_CFLAGS_W1_20200930) -DKBUILD_EXTRA_WARN1 > > else > > -- > 2.28.0 > > -- > You received this message because you are subscribed to the Google Groups "Clang Built Linux" group. > To unsubscribe from this group and stop receiving emails from it, send an email to clang-built-linux+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/clang-built-linux/20201001011232.4050282-2-andrew%40lunn.ch. -- Thanks, ~Nick Desaulniers
