Nathan, thank you a lot for helping with the patch! I will send an updated patch that integrates your suggestion shortly. -Rong On Fri, Nov 8, 2024 at 9:46 AM Nathan Chancellor <nathan@xxxxxxxxxx> wrote: > > Hi Rong, > > Thanks for the quick patch! > > On Thu, Nov 07, 2024 at 09:10:30PM -0800, Rong Xu wrote: > > The '-fbasic-block-sections=labels' option has been deprecated with > > the following llvm patch: > > https://github.com/llvm/llvm-project/pull/110039 > > > > The old option still works, but with a warning like > > clang: warning: argument '-fbasic-block-sections=labels' \ > > is deprecated, use '-fbasic-block-address-map' instead [-Wdeprecated] > > > > Currently, the option change is only in the ToT clang (v20) and not yet > > released in v19. > > I think this whole block could be a little easier to read and understand > with some more standard kernel commit message practices. I would combine > the first and third block into one sentence and I would unwrap the > warning text (it is okay to be long for a little clarity). Perhaps > something like this? > > | The '-fbasic-block-sections=labels' option has been deprecated in tip of > | tree clang (20.0.0) [1]. While the option still works, a warning is > | emitted: > | > | clang: warning: argument '-fbasic-block-sections=labels' is deprecated, use '-fbasic-block-address-map' instead [-Wdeprecated] > > then putting: > > | Link: https://github.com/llvm/llvm-project/pull/110039 [1] > > right above your Signoff. > > > This patch adds a check to the Makefile to set the proper option. > > Try to avoid saying "this patch" in kernel commit messages, it is > implicit. It would be cleaner to say something like: > > | Add a version check to set the proper option. > > You can see some more commit message tips in sections 4.2.3 to 4.2.6 in > the tip documentation: > > https://docs.kernel.org/process/maintainer-tip.html#changelog > > > If the option change is later integrated in v19.x, we need to update the > > check accordingly. > > I think it is worth dropping this sentence entirely, as I would argue > that it is pretty unlikely that this option gets backported to > release/19.x, since it would basically accelerate the deprecation > timeline, which seems unreasonable to do in a stable release. > These are excellent suggestions that make the message more clear. I'll update the patch description. > > Signed-off-by: Rong Xu <xur@xxxxxxxxxx> > > Reported-by: Nathan Chancellor <nathan@xxxxxxxxxx> > > --- > > scripts/Makefile.propeller | 14 ++++++++++++-- > > 1 file changed, 12 insertions(+), 2 deletions(-) > > > > diff --git a/scripts/Makefile.propeller b/scripts/Makefile.propeller > > index 344190717e47..1a68ea0d1fe4 100644 > > --- a/scripts/Makefile.propeller > > +++ b/scripts/Makefile.propeller > > @@ -5,7 +5,13 @@ ifdef CLANG_PROPELLER_PROFILE_PREFIX > > CFLAGS_PROPELLER_CLANG := -fbasic-block-sections=list=$(CLANG_PROPELLER_PROFILE_PREFIX)_cc_profile.txt -ffunction-sections > > KBUILD_LDFLAGS += --symbol-ordering-file=$(CLANG_PROPELLER_PROFILE_PREFIX)_ld_profile.txt --no-warn-symbol-ordering > > else > > - CFLAGS_PROPELLER_CLANG := -fbasic-block-sections=labels > > + # Staring with clang v20, the '-fbasic-block-sections=labels' option is > > + # deprecated. Use the recommended '-fbasic-block-address-map' option. > > Might be worth linking the specific change here for archeology sake. > I will add the link in the comments. > > + ifeq ($(call clang-min-version, 200000),y) > > + CFLAGS_PROPELLER_CLANG := -fbasic-block-address-map > > + else > > + CFLAGS_PROPELLER_CLANG := -fbasic-block-sections=labels > > + endif > > endif > > > > # Propeller requires debug information to embed module names in the profiles. > > @@ -21,7 +27,11 @@ ifdef CONFIG_LTO_CLANG_THIN > > ifdef CLANG_PROPELLER_PROFILE_PREFIX > > KBUILD_LDFLAGS += --lto-basic-block-sections=$(CLANG_PROPELLER_PROFILE_PREFIX)_cc_profile.txt > > else > > - KBUILD_LDFLAGS += --lto-basic-block-sections=labels > > + ifeq ($(call clang-min-version, 200000),y) > > Would it be better/more accurate to check the LLD version here? I doubt > it would really happen but it is possible for someone to have LLVM=1 > (using their system wide ld.lld and LLVM tools) and CC=clang-20 to just > use an updated clang. Perhaps: > > ifeq ($(call test-ge, $(CONFIG_LLD_VERSION), 200000),y) > > here? I agree: checking the LLD version makes more sense here. > > > + KBUILD_LDFLAGS += --lto-basic-block-address-map > > + else > > + KBUILD_LDFLAGS += --lto-basic-block-sections=labels > > + endif > > endif > > endif > > > > > > base-commit: 0dcc2d1066150787017a71f035145c566597dec7 > > -- > > 2.47.0.277.g8800431eea-goog > >
