By the way, I've found that warning while working on the older kernel with older gcc (ver. 3.4.4). The modern gcc (ver. 4.5.4) does not emit that warning no matter how hard I try. For example, it does not warn even with the following line in the drivers/uio/Makefile:
ccflags-$(CONFIG_UIO) += -O2 -Wall -Wextra -Wuninitialized In that case the actual command line looks like (from "make V=1" output): gcc -Wp,-MD,drivers/uio/.uio.o.d -nostdinc -isystem /usr/lib/gcc/x86_64-pc-linux-gnu/4.5.4/include -I/home/vitas/Progs/net-next/net-next/arch/x86/include -Iarch/x86/include/generated -Iinclude -I/home/vitas/Progs/net-next/net-next/arch/x86/include/uapi -Iarch/x86/include/generated/uapi -I/home/vitas/Progs/net-next/net-next/include/uapi -Iinclude/generated/uapi -include /home/vitas/Progs/net-next/net-next/include/linux/kconfig.h -D__KERNEL__ -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -Werror-implicit-function-declaration -Wno-format-security -fno-delete-null-pointer-checks -O2 -m64 -mtune=generic -mno-red-zone -mcmodel=kernel -funit-at-a-time -maccumulate-outgoing-args -DCONFIG_AS_CFI=1 -DCONFIG_AS_CFI_SIGNAL_FRAME=1 -DCONFIG_AS_CFI_SECTIONS=1 -DCONFIG_AS_FXSAVEQ=1 -DCONFIG_AS_AVX=1 -pipe -Wno-sign-compare -fno-asynchronous-unwind-tables -mno-sse -mno-mmx -mno-sse2 -mno-3dnow -mno-avx -Wframe-larger-than=2048 -fno-stack-protector -fno-omit-frame-pointer -fno-optimize-sibling-calls -Wdeclaration-after-statement -Wno-pointer-sign -fno-strict-overflow -fconserve-stack -DCC_HAVE_ASM_GOTO -O2 -Wall -Wextra -Wuninitialized -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(uio)" -D"KBUILD_MODNAME=KBUILD_STR(uio)" -c -o drivers/uio/uio.o drivers/uio/uio.c I wander why doesn't modern gcc warn about obvious use of uninitialized variable. Is it some known regression in gcc? -- With Best Regards, Vitalii Demianets -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
