On Thu, Dec 01, 2011 at 03:31:38PM +0700, tknv wrote:

I could not find that WERROR override code at my kernels...

Sorry delay it, I did make V=1. There are three kinds test. All targets are ARM. All Makefiles(top of kernel tree)-KBUILD_CFLAGS are same. KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \ -fno-strict-aliasing -fno-common \ -Wno-format-security \ -fno-delete-null-pointer-checks

I think linaro Werror behaviour is different or I need to add FLAGS more.

Compile CM-kernel with android SDK make -f scripts/Makefile.build obj=drivers/net/wireless/bcm4329 rm -f drivers/net/wireless/bcm4329/built-in.o; /home/tknv/android/Oxygen/prebuil t/linux-x86/toolchain/arm-eabi-4.4.3/bin/arm-eabi-ar rcs drivers/net/wireless/bcm43 29/built-in.o /home/tknv/android/Oxygen/prebuilt/linux-x86/toolchain/arm-eabi-4.4.3/bin/arm-eab i-gcc -Wp,-MD,drivers/net/wireless/bcm4329/.dhd_linux.o.d -nostdinc -isystem /home /tknv/android/Oxygen/prebuilt/linux-x86/toolchain/arm-eabi-4.4.3/bin/../lib/gcc/arm -eabi/4.4.3/include -I/home/tknv/android/SuperSonic/kernels/CM-kernel/arch/arm/incl ude -Iinclude -include include/generated/autoconf.h -D__KERNEL__ -mlittle-endian - Iarch/arm/mach-msm/include -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-st rict-aliasing -fno-common -Wno-format-security -fno-delete-null-pointer-checks -Os -marm -mabi=aapcs-linux -mno-thumb-interwork -funwind-tables -D__LINUX_ARM_ARCH__=7 -march=armv7-a -msoft-float -Uarm -Wframe-larger-than=1024 -fno-stack-protector -f omit-frame-pointer -Wdeclaration-after-statement -Wno-pointer-sign -fno-strict-over flow -fno-dwarf2-cfi-asm -fconserve-stack -DLINUX -DBCMDRIVER -DBCMDONGLEHOST -DDHD THREAD -DBCMWPA2 -DUNRELEASEDCHIP -Dlinux -DDHD_SDALIGN=64 -DMAX_HDR_READ=64 -DDHD_ FIRSTREAD=64 -DDHD_GPL -DDHD_SCHED -DBDC -DTOE -DDHD_BCMEVENTS -DSHOW_EVENTS -DBCMS DIO -DDHD_GPL -DBCMLXSDMMC -DBCMPLATFORM_BUS -Wall -Wstrict-prototypes -Werror -DOO B_INTR_ONLY -DCUSTOMER_HW2 -DDHD_USE_STATIC_BUF -DMMC_SDIO_ABORT -DDHD_DEBUG_TRAP - DSOFTAP -DEMBEDDED_PLATFORM -DARP_OFFLOAD_SUPPORT -DPKT_FILTER_SUPPORT -DGET_CUSTOM _MAC_ENABLE -DSET_RANDOM_MAC_SOFTAP -DHW_OOB -Idrivers/net/wireless/bcm4329 -Idrive rs/net/wireless/bcm4329/include -DMODULE -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=K BUILD_STR(dhd_linux)" -D"KBUILD_MODNAME=KBUILD_STR(bcm4329)" -c -o drivers/net/wi reless/bcm4329/dhd_linux.o drivers/net/wireless/bcm4329/dhd_linux. ... [1]+ Done make V=1 > build.log 2>&1

Compile CM-kernel with linaro. make -f scripts/Makefile.build obj=drivers/net/wireless/bcm4329 rm -f drivers/net/wireless/bcm4329/built-in.o; /usr/bin/arm-linux-gnueabi-ar rcs drivers/net/wireless/bcm4329/built-in.o /usr/bin/arm-linux-gnueabi-gcc -Wp,-MD,drivers/net/wireless/bcm4329/.dhd_linux.o.d -nostdinc -isystem /usr/lib/gcc/arm-linux-gnueabi/4.6.1/include -I/home/tknv/android/SuperSonic/kernels/CM-kernel/arch/arm/include -Iinclude -include include/generated/autoconf.h -D__KERNEL__ -mlittle-endian -Iarch/arm/mach-msm/include -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -Wno-format-security -fno-delete-null-pointer-checks -Os -marm -mabi=aapcs-linux -mno-thumb-interwork -funwind-tables -D__LINUX_ARM_ARCH__=7 -march=armv7-a -msoft-float -Uarm -Wframe-larger-than=1024 -fno-stack-protector -fomit-frame-pointer -Wdeclaration-after-statement -Wno-pointer-sign -fno-strict-overflow -fno-dwarf2-cfi-asm -fconserve-stack -DLINUX -DBCMDRIVER -DBCMDONGLEHOST -DDHDTHREAD -DBCMWPA2 -DUNRELEASEDCHIP -Dlinux -DDHD_SDALIGN=64 -DMAX_HDR_READ=64 -DDHD_FIRSTREAD=64 -DDHD_GPL -DDHD_SCHED -DBDC -DTOE -DDHD_BCMEVENTS -DSHOW_EVENTS -DBCMSDIO -DDHD_GPL -DBCMLXSDMMC -DBCMPLATFORM_BUS -Wall -Wstrict-prototypes -Werror -DOOB_INTR_ONLY -DCUSTOMER_HW2 -DDHD_USE_STATIC_BUF -DMMC_SDIO_ABORT -DDHD_DEBUG_TRAP -DSOFTAP -DEMBEDDED_PLATFORM -DARP_OFFLOAD_SUPPORT -DPKT_FILTER_SUPPORT -DGET_CUSTOM_MAC_ENABLE -DSET_RANDOM_MAC_SOFTAP -DHW_OOB -Idrivers/net/wireless/bcm4329 -Idrivers/net/wireless/bcm4329/include -DMODULE -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(dhd_linux)" -D"KBUILD_MODNAME=KBUILD_STR(bcm4329)" -c -o drivers/net/wireless/bcm4329/dhd_linux.o drivers/net/wireless/bcm4329/dhd_linux.c drivers/net/wireless/bcm4329/dhd_linux.c: In function ‘ dhd_rx_frame’: drivers/net/wireless/bcm4329/dhd_linux.c:1282:24: error: variable ‘save_pktbuf’ set but not used [-Werror=unused-but-set-variable] drivers/net/wireless/bcm4329/dhd_linux.c: In function ‘ dhd_os_wd_timer’: drivers/net/wireless/bcm4329/dhd_linux.c:2737:14: error: variable ‘save_dhd_watchdog_ms’ set but not used [-Werror=unused-but-set-variable] cc1: all warnings being treated as errors

 make[4]: *** [drivers/net/wireless/bcm4329/dhd_linux.o] Error 1
 make[3]: *** [drivers/net/wireless/bcm4329] Error 2
 make[2]: *** [drivers/net/wireless] Error 2
 make[1]: *** [drivers/net] Error 2
 make: *** [drivers] Error 2
 ^C[1]+  Exit 2                  make V=1 > build.log 2>&1

Compile tiamatat-kernel with linaro. make -f scripts/Makefile.build obj=drivers/net/wireless/bcm4329 /usr/bin/arm-linux-gnueabi-gcc -Wp,-MD,drivers/net/wireless/bcm4329/.dhd_linux.o.d -nostdinc -isystem /usr/lib/gcc/arm-linux-gnueabi/4.6.1/include -I/home/tknv/android/SuperSonic/kernels/tiamat-kernel/arch/arm/include -Iinclude -include include/generated/autoconf.h -D__KERNEL__ -mlittle-endian -Iarch/arm/mach-msm/include -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -Wno-format-security -fno-delete-null-pointer-checks -Os -marm -fno-dwarf2-cfi-asm -fno-omit-frame-pointer -mapcs -mno-sched-prolog -mabi=aapcs-linux -mno-thumb-interwork -D__LINUX_ARM_ARCH__=7 -march=armv7-a -mhard-float -Uarm -Wframe-larger-than=1024 -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 -DLINUX -DBCMDRIVER -DBCMDONGLEHOST -DDHDTHREAD -DBCMWPA2 -DUNRELEASEDCHIP -Dlinux -DDHD_SDALIGN=64 -DMAX_HDR_READ=64 -DDHD_FIRSTREAD=64 -DDHD_GPL -DDHD_SCHED -DBDC -DTOE -DDHD_BCMEVENTS -DSHOW_EVENTS -DBCMSDIO -DDHD_GPL -DBCMLXSDMMC -DBCMPLATFORM_BUS -Wall -Wstrict-prototypes -Werror -DOOB_INTR_ONLY -DCUSTOMER_HW2 -DDHD_USE_STATIC_BUF -DMMC_SDIO_ABORT -DDHD_DEBUG_TRAP -DSOFTAP -DEMBEDDED_PLATFORM -DARP_OFFLOAD_SUPPORT -DPKT_FILTER_SUPPORT -DGET_CUSTOM_MAC_ENABLE -DSET_RANDOM_MAC_SOFTAP -DCSCAN -DHW_OOB -DKEEP_ALIVE -DPNO_SUPPORT -Idrivers/net/wireless/bcm4329 -Idrivers/net/wireless/bcm4329/include -DMODULE -DMODULE -march=armv7-a -mfpu=vfpv3 -ftree-vectorize -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(dhd_linux)" -D"KBUILD_MODNAME=KBUILD_STR(bcm4329)" -c -o drivers/net/wireless/bcm4329/dhd_linux.o drivers/net/wireless/bcm4329/dhd_linux.c drivers/net/wireless/bcm4329/dhd_linux.c: In function ‘dhd_rx_frame’ : drivers/net/wireless/bcm4329/dhd_linux.c:1256:24: error: variable ‘ save_pktbuf’ set but not used [-Werror=unused-but-set-variable] cc1: all warnings being treated as errors

make[4]: *** [drivers/net/wireless/bcm4329/dhd_linux.o] Error 1 make[3]: *** [drivers/net/wireless/bcm4329] Error 2 make[2]: *** [drivers/net/wireless] Error 2 make[1]: *** [drivers/net] Error 2 make: *** [drivers] Error 2 ^C[1]+ Exit 2 make V=1 > build.log 2>&1

OK, so the reason why you can't turn -Werror off is because drivers/net/wireless/bcm4329/Makefile adds it again:

DHDCFLAGS = -DLINUX -DBCMDRIVER -DBCMDONGLEHOST -DDHDTHREAD -DBCMWPA2 \ -DUNRELEASEDCHIP -Dlinux -DDHD_SDALIGN=64 -DMAX_HDR_READ=64 \ -DDHD_FIRSTREAD=64 -DDHD_GPL -DDHD_SCHED -DBDC -DTOE -DDHD_BCMEVENTS \ -DSHOW_EVENTS -DBCMSDIO -DDHD_GPL -DBCMLXSDMMC -DBCMPLATFORM_BUS \ -Wall -Wstrict-prototypes -Werror -DOOB_INTR_ONLY -DCUSTOMER_HW2 \ -DDHD_USE_STATIC_BUF -DMMC_SDIO_ABORT -DDHD_DEBUG_TRAP -DSOFTAP \ -DEMBEDDED_PLATFORM -DARP_OFFLOAD_SUPPORT -DPKT_FILTER_SUPPORT \ -DGET_CUSTOM_MAC_ENABLE -DSET_RANDOM_MAC_SOFTAP -DCSCAN -DHW_OOB \ -DKEEP_ALIVE -DPNO_SUPPORT \ -Idrivers/net/wireless/bcm4329 -Idrivers/net/wireless/bcm4329/include

EXTRA_CFLAGS = $(DHDCFLAGS)

Kbuild doesn't allow you to override such things from the top level.

Adding -Werror overrides any preceding -Wno-error flag.

-Werror really should only be added in subdirectory Makefiles if the code in that directory is super-clean. The exact behaviour of GCC with -Werror *will* change between different compiler versions -- this is not a bug. It explicitly allows GCC to fail to compile code which might be correct.

There seems to be no good way to override -Werror in a subdirectory Makefile from higher-level Makefiles. You may be able to remove the error behaviour for individual warnings with -Wno-error=<warning>, but it's not really a good idea to do this at the top level because it will affect the whole kernel.

So far as I can see, the warnings/errors you get probably indicate real issues in the code. It doesn't look like a compiler bug, or a problem with Kbuild -- it's just an effect of the way the writers of that subdirectory wrote their Makefile.

If you have not already done so, you should check for newer versions of the code which may fix the problems. If there is no newer version, it would be a good idea to fix the source code issues and propose those changes for merging so that the problem gets solved for everyone.

You can also simply remove -Werror from DHDCFLAGS in your local build tree. This will allow you to build the kernel, but it won't prevent other people from encountering the same problem.

Since this appears to be an issue with an Android kernel tree, I suggest if you have more questions on this you should reply via linaro-dev@lists.linaro.org, or ask questions on the #linaro or #linaro-android channels on IRC at chat.freenode.net if you need additional help.

Cheers ---Dave