From 095fbca0a94930b58f977284ef1b759b98700f8b Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 26 Oct 2020 23:03:13 +0100 Subject: Makefile.extrawarn: move -Wcast-align to W=3 This warning behaves differently depending on the architecture and compiler. Using x86 gcc, we get no output at all because gcc knows the architecture can handle unaligned accesses. Using x86 clang, or gcc on an architecture that needs to manually deal with unaligned accesses, the build log is completely flooded with these warnings, as they are commonly invoked by inline functions of networking headers, e.g. include/linux/skbuff.h:1426:26: warning: cast increases required alignment of target type [-Wcast-align] The compiler is correct to point this out, as we are dealing with undefined behavior that does cause problems in practice, but there is also no good way to rewrite the code in commonly included headers to a safer method. Signed-off-by: Arnd Bergmann Reviewed-by: Nathan Chancellor Signed-off-by: Masahiro Yamada --- scripts/Makefile.extrawarn | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/Makefile.extrawarn') diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn index 95e4cdb94fe9..6baee1200615 100644 --- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -60,7 +60,6 @@ endif # ifneq ($(findstring 2, $(KBUILD_EXTRA_WARN)),) -KBUILD_CFLAGS += -Wcast-align KBUILD_CFLAGS += -Wdisabled-optimization KBUILD_CFLAGS += -Wnested-externs KBUILD_CFLAGS += -Wshadow @@ -80,6 +79,7 @@ endif ifneq ($(findstring 3, $(KBUILD_EXTRA_WARN)),) KBUILD_CFLAGS += -Wbad-function-cast +KBUILD_CFLAGS += -Wcast-align KBUILD_CFLAGS += -Wcast-qual KBUILD_CFLAGS += -Wconversion KBUILD_CFLAGS += -Wpacked -- cgit v1.3-14-g43fede From c93e4aeed1be5b99715a9127f5b38d6b4ab9e5d7 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 24 Nov 2020 16:43:17 +0100 Subject: Makefile.extrawarn: remove -Wnested-externs warning The -Wnested-externs warning has become useless with gcc, since this warns every time that BUILD_BUG_ON() or similar macros are used. With clang, the warning option does nothing to start with, so just remove it entirely. Suggested-by: Nathan Chancellor Signed-off-by: Arnd Bergmann Reviewed-by: Nathan Chancellor Signed-off-by: Masahiro Yamada --- scripts/Makefile.extrawarn | 1 - 1 file changed, 1 deletion(-) (limited to 'scripts/Makefile.extrawarn') diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn index 6baee1200615..d53825503874 100644 --- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -61,7 +61,6 @@ endif ifneq ($(findstring 2, $(KBUILD_EXTRA_WARN)),) KBUILD_CFLAGS += -Wdisabled-optimization -KBUILD_CFLAGS += -Wnested-externs KBUILD_CFLAGS += -Wshadow KBUILD_CFLAGS += $(call cc-option, -Wlogical-op) KBUILD_CFLAGS += -Wmissing-field-initializers -- cgit v1.3-14-g43fede