| Message ID | 20240531193838.108454-6-jhubbard@nvidia.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 54df8db8c658f29a35e3bfe651e49f87f72dec76 |
| Headers | show |
| Series | selftests/x86: fix build errors and warnings found via clang | expand |
On 5/31/24 12:38 PM, John Hubbard wrote: ... > diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile > index d0bb32bd5538..5c8757a25998 100644 > --- a/tools/testing/selftests/x86/Makefile > +++ b/tools/testing/selftests/x86/Makefile > @@ -40,6 +40,13 @@ CFLAGS := -O2 -g -std=gnu99 -pthread -Wall $(KHDR_INCLUDES) > # call32_from_64 in thunks.S uses absolute addresses. > ifeq ($(CAN_BUILD_WITH_NOPIE),1) > CFLAGS += -no-pie > + > +ifneq ($(LLVM),) > +# clang only wants to see -no-pie during linking. Here, we don't have a separate > +# linking stage, so a compiler warning is unavoidable without (wastefully) > +# restructuring the Makefile. Avoid this by simply disabling that warning. > +CFLAGS += -Wno-unused-command-line-argument > +endif > endif > > define gen-target-rule-32 This actually can be improved slightly, as per our latest tentative decision about how to handle both LLVM=1 and CC=clang cases [1]. If this series goes via Shuah's next tree, then I can put the CC_IS_CLANG fix from [1] on top of previous patches, that will work nicely. In other words, I think we can use this series as-is, and let the CC_IS_CLANG fix proceed just after that. Because it gets better a piece at a time: first we get rid of the warning for most cases, then we get rid of it for the odd "make CC=clang" case as well. [1] https://lore.kernel.org/6b32399f-d9c6-4df5-b1e5-755ef4acf25d@nvidia.com thanks,
diff --git a/tools/testing/selftests/x86/Makefile b/tools/testing/selftests/x86/Makefile index d0bb32bd5538..5c8757a25998 100644 --- a/tools/testing/selftests/x86/Makefile +++ b/tools/testing/selftests/x86/Makefile @@ -40,6 +40,13 @@ CFLAGS := -O2 -g -std=gnu99 -pthread -Wall $(KHDR_INCLUDES) # call32_from_64 in thunks.S uses absolute addresses. ifeq ($(CAN_BUILD_WITH_NOPIE),1) CFLAGS += -no-pie + +ifneq ($(LLVM),) +# clang only wants to see -no-pie during linking. Here, we don't have a separate +# linking stage, so a compiler warning is unavoidable without (wastefully) +# restructuring the Makefile. Avoid this by simply disabling that warning. +CFLAGS += -Wno-unused-command-line-argument +endif endif define gen-target-rule-32
When building with clang, via: make LLVM=1 -C tools/testing/selftests ...clang warns that -no-pie is "unused during compilation". This occurs because clang only wants to see -no-pie during linking. Here, we don't have a separate linking stage, so a compiler warning is unavoidable without (wastefully) restructuring the Makefile. Avoid the warning by simply disabling that warning, for clang builds. Signed-off-by: John Hubbard <jhubbard@nvidia.com> --- tools/testing/selftests/x86/Makefile | 7 +++++++ 1 file changed, 7 insertions(+)