From afe956c577b2d5a3d9834e4424587c1ebcf90c4c Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Thu, 26 Mar 2020 12:41:55 -0700 Subject: kbuild: Enable -Wtautological-compare Currently, we disable -Wtautological-compare, which in turn disables a bunch of more specific tautological comparison warnings that are useful for the kernel such as -Wtautological-bitwise-compare. See clang's documentation below for the other warnings that are suppressed by -Wtautological-compare. Now that all of the major/noisy warnings have been fixed, enable -Wtautological-compare so that more issues can be caught at build time by various continuous integration setups. -Wtautological-constant-out-of-range-compare is kept disabled under a normal build but visible at W=1 because there are places in the kernel where a constant or variable size can change based on the kernel configuration. These are not fixed in a clean/concise way and the ones I have audited so far appear to be harmless. It is not a subgroup but rather just one warning so we do not lose out on much coverage by default. Link: https://github.com/ClangBuiltLinux/linux/issues/488 Link: http://releases.llvm.org/10.0.0/tools/clang/docs/DiagnosticsReference.html#wtautological-compare Link: https://bugs.llvm.org/show_bug.cgi?id=42666 Signed-off-by: Nathan Chancellor Signed-off-by: Masahiro Yamada --- scripts/Makefile.extrawarn | 1 + 1 file changed, 1 insertion(+) (limited to 'scripts') diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn index ca08f2fe7c34..4aea7cf71d11 100644 --- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -49,6 +49,7 @@ KBUILD_CFLAGS += -Wno-format KBUILD_CFLAGS += -Wno-sign-compare KBUILD_CFLAGS += -Wno-format-zero-length KBUILD_CFLAGS += $(call cc-disable-warning, pointer-to-enum-cast) +KBUILD_CFLAGS += -Wno-tautological-constant-out-of-range-compare endif endif -- cgit v1.2.3