Unverified Commit df493f21 authored Mar 25, 2020 by Masahiro Yamada Committed by LuK1337 Sep 28, 2025

kbuild: add -Wall to KBUILD_HOSTCXXFLAGS



Add -Wall to catch more warnings for C++ host programs.

When I submitted the previous version, the 0-day bot reported
-Wc++11-compat warnings for old GCC:

  HOSTCXX -fPIC scripts/gcc-plugins/latent_entropy_plugin.o
In file included from /usr/lib/gcc/x86_64-linux-gnu/4.8/plugin/include/tm.h:28:0,
                 from scripts/gcc-plugins/gcc-common.h:15,
                 from scripts/gcc-plugins/latent_entropy_plugin.c:78:
/usr/lib/gcc/x86_64-linux-gnu/4.8/plugin/include/config/elfos.h:102:21: warning: C++11 requires a space between string literal and macro [-Wc++11-compat]
    fprintf ((FILE), "%s"HOST_WIDE_INT_PRINT_UNSIGNED"\n",\
                     ^
/usr/lib/gcc/x86_64-linux-gnu/4.8/plugin/include/config/elfos.h:170:24: warning: C++11 requires a space between string literal and macro [-Wc++11-compat]
       fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",%u\n",  \
                        ^
In file included from /usr/lib/gcc/x86_64-linux-gnu/4.8/plugin/include/tm.h:42:0,
                 from scripts/gcc-plugins/gcc-common.h:15,
                 from scripts/gcc-plugins/latent_entropy_plugin.c:78:
/usr/lib/gcc/x86_64-linux-gnu/4.8/plugin/include/defaults.h:126:24: warning: C++11 requires a space between string literal and macro [-Wc++11-compat]
       fprintf ((FILE), ","HOST_WIDE_INT_PRINT_UNSIGNED",%u\n",  \
                        ^

The source of the warnings is in the plugin headers, so we have no
control of it. I just suppressed them by adding -Wno-c++11-compat to
scripts/gcc-plugins/Makefile.

Change-Id: I3cb616b5dbb4e6c55a537453807da86f473f73d8
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>

parent a2dab3fc

Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -415,7 +415,7 @@ endif
		KBUILD_HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 \
		-fomit-frame-pointer -std=gnu89 $(HOST_LFS_CFLAGS) \
		$(HOSTCFLAGS)
		KBUILD_HOSTCXXFLAGS := -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
		KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS)
		KBUILD_HOSTLDFLAGS := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
		KBUILD_HOSTLDLIBS := $(HOST_LFS_LIBS) $(HOSTLDLIBS)

scripts/gcc-plugins/Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -10,7 +10,7 @@ else
		HOSTLIBS := hostcxxlibs
		HOST_EXTRACXXFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu++98 -fno-rtti
		HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb
		HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable
		HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable -Wno-c++11-compat
		HOST_EXTRACXXFLAGS += -Wno-format-diag
		export HOST_EXTRACXXFLAGS
		endif