Re: [PATCH] btrfs: Use immediate assignment when referencing cc-option
On Tue, Mar 16, 2021 at 03:46:10PM -0700, Victor Erminpour wrote: > Calling cc-option will use KBUILD_CFLAGS, which when lazy setting > subdir-ccflags-y produces the following build error: > > scripts/Makefile.lib:10: *** Recursive variable `KBUILD_CFLAGS' \ > references itself (eventually). Stop. > > Use := assignment to subdir-ccflags-y when referencing cc-option. > This causes make to also evaluate += immediately, cc-option > calls are done right away and we don't end up with KBUILD_CFLAGS > referencing itself. > > Signed-off-by: Victor Erminpour > --- > fs/btrfs/Makefile | 8 > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile > index b634c42115ea..3dba1336fa95 100644 > --- a/fs/btrfs/Makefile > +++ b/fs/btrfs/Makefile > @@ -7,10 +7,10 @@ subdir-ccflags-y += -Wmissing-format-attribute > subdir-ccflags-y += -Wmissing-prototypes > subdir-ccflags-y += -Wold-style-definition > subdir-ccflags-y += -Wmissing-include-dirs > -subdir-ccflags-y += $(call cc-option, -Wunused-but-set-variable) > -subdir-ccflags-y += $(call cc-option, -Wunused-const-variable) > -subdir-ccflags-y += $(call cc-option, -Wpacked-not-aligned) > -subdir-ccflags-y += $(call cc-option, -Wstringop-truncation) > +subdir-ccflags-y := $(call cc-option, -Wunused-but-set-variable) > +subdir-ccflags-y := $(call cc-option, -Wunused-const-variable) > +subdir-ccflags-y := $(call cc-option, -Wpacked-not-aligned) > +subdir-ccflags-y := $(call cc-option, -Wstringop-truncation) But this overwrites all the previously accumulated values from += so effectively there's only the last one, no? That's not what we want.
Re: [PATCH] btrfs: Use immediate assignment when referencing cc-option
On 17.03.21 г. 0:46 ч., Victor Erminpour wrote: > Calling cc-option will use KBUILD_CFLAGS, which when lazy setting > subdir-ccflags-y produces the following build error: > > scripts/Makefile.lib:10: *** Recursive variable `KBUILD_CFLAGS' \ > references itself (eventually). Stop. > > Use := assignment to subdir-ccflags-y when referencing cc-option. > This causes make to also evaluate += immediately, cc-option > calls are done right away and we don't end up with KBUILD_CFLAGS > referencing itself. > > Signed-off-by: Victor Erminpour > --- > fs/btrfs/Makefile | 8 > 1 file changed, 4 insertions(+), 4 deletions(-) > > diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile > index b634c42115ea..3dba1336fa95 100644 > --- a/fs/btrfs/Makefile > +++ b/fs/btrfs/Makefile > @@ -7,10 +7,10 @@ subdir-ccflags-y += -Wmissing-format-attribute > subdir-ccflags-y += -Wmissing-prototypes > subdir-ccflags-y += -Wold-style-definition > subdir-ccflags-y += -Wmissing-include-dirs > -subdir-ccflags-y += $(call cc-option, -Wunused-but-set-variable) > -subdir-ccflags-y += $(call cc-option, -Wunused-const-variable) > -subdir-ccflags-y += $(call cc-option, -Wpacked-not-aligned) > -subdir-ccflags-y += $(call cc-option, -Wstringop-truncation) > +subdir-ccflags-y := $(call cc-option, -Wunused-but-set-variable) > +subdir-ccflags-y := $(call cc-option, -Wunused-const-variable) > +subdir-ccflags-y := $(call cc-option, -Wpacked-not-aligned) > +subdir-ccflags-y := $(call cc-option, -Wstringop-truncation) > # The following turn off the warnings enabled by -Wextra > subdir-ccflags-y += -Wno-missing-field-initializers > subdir-ccflags-y += -Wno-sign-compare > Why does this patch change only some assignments and others are left as they were?
Re: [PATCH] btrfs: Use immediate assignment when referencing cc-option
On 17/03/2021 06:46, Victor Erminpour wrote: Calling cc-option will use KBUILD_CFLAGS, which when lazy setting subdir-ccflags-y produces the following build error: scripts/Makefile.lib:10: *** Recursive variable `KBUILD_CFLAGS' \ references itself (eventually). Stop. Use := assignment to subdir-ccflags-y when referencing cc-option. This causes make to also evaluate += immediately, cc-option calls are done right away and we don't end up with KBUILD_CFLAGS referencing itself. Thanks for the patch. Reviewed-by: Anand Jain Signed-off-by: Victor Erminpour --- fs/btrfs/Makefile | 8 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile index b634c42115ea..3dba1336fa95 100644 --- a/fs/btrfs/Makefile +++ b/fs/btrfs/Makefile @@ -7,10 +7,10 @@ subdir-ccflags-y += -Wmissing-format-attribute subdir-ccflags-y += -Wmissing-prototypes subdir-ccflags-y += -Wold-style-definition subdir-ccflags-y += -Wmissing-include-dirs -subdir-ccflags-y += $(call cc-option, -Wunused-but-set-variable) -subdir-ccflags-y += $(call cc-option, -Wunused-const-variable) -subdir-ccflags-y += $(call cc-option, -Wpacked-not-aligned) -subdir-ccflags-y += $(call cc-option, -Wstringop-truncation) +subdir-ccflags-y := $(call cc-option, -Wunused-but-set-variable) +subdir-ccflags-y := $(call cc-option, -Wunused-const-variable) +subdir-ccflags-y := $(call cc-option, -Wpacked-not-aligned) +subdir-ccflags-y := $(call cc-option, -Wstringop-truncation) # The following turn off the warnings enabled by -Wextra subdir-ccflags-y += -Wno-missing-field-initializers subdir-ccflags-y += -Wno-sign-compare
