forked from Minki/linux
mainlining shenanigans
7ed1c1901f
Currently a number of Makefiles break when used with toolchains that pass extra flags in CC and other cross-compile related variables (such as --sysroot). Thus we get this error when we use a toolchain that puts --sysroot in the CC var: ~/src/linux/tools$ make iio [snip] iio_event_monitor.c:18:10: fatal error: unistd.h: No such file or directory #include <unistd.h> ^~~~~~~~~~ This occurs because we clobber several env vars related to cross-compiling with lines like this: CC = $(CROSS_COMPILE)gcc Although this will point to a valid cross-compiler, we lose any extra flags that might exist in the CC variable, which can break toolchains that rely on them (for example, those that use --sysroot). This easily shows up using a Yocto SDK: $ . [snip]/sdk/environment-setup-cortexa8hf-neon-poky-linux-gnueabi $ echo $CC arm-poky-linux-gnueabi-gcc -march=armv7-a -mfpu=neon -mfloat-abi=hard -mcpu=cortex-a8 --sysroot=[snip]/sdk/sysroots/cortexa8hf-neon-poky-linux-gnueabi $ echo $CROSS_COMPILE arm-poky-linux-gnueabi- $ echo ${CROSS_COMPILE}gcc krm-poky-linux-gnueabi-gcc Although arm-poky-linux-gnueabi-gcc is a cross-compiler, we've lost the --sysroot and other flags that enable us to find the right libraries to link against, so we can't find unistd.h and other libraries and headers. Normally with the --sysroot flag we would find unistd.h in the sdk directory in the sysroot: $ find [snip]/sdk/sysroots -path '*/usr/include/unistd.h' [snip]/sdk/sysroots/cortexa8hf-neon-poky-linux-gnueabi/usr/include/unistd.h The perf Makefile adds CC = $(CROSS_COMPILE)gcc if and only if CC is not already set, and it compiles correctly with the above toolchain. So, generalize the logic that perf uses in the common Makefile and remove the manual CC = $(CROSS_COMPILE)gcc lines from each Makefile. Note that this patch does not fix cross-compile for all the tools (some have other bugs), but it does fix it for all except usb and acpi, which still have other unrelated issues. I tested both with and without the patch on native and cross-build and there appear to be no regressions. Link: http://lkml.kernel.org/r/20180107214028.23771-1-martin@martingkelly.com Signed-off-by: Martin Kelly <martin@martingkelly.com> Acked-by: Mark Brown <broonie@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Jonathan Cameron <jic23@kernel.org> Cc: Pali Rohar <pali.rohar@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Robert Moore <robert.moore@intel.com> Cc: Lv Zheng <lv.zheng@intel.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Valentina Manea <valentina.manea.m@gmail.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Mario Limonciello <mario.limonciello@dell.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.