--- /dev/null
+From 7ed1c1901fe52e6c5828deb155920b44b0adabb1 Mon Sep 17 00:00:00 2001
+From: Martin Kelly <martin@martingkelly.com>
+Date: Wed, 21 Feb 2018 14:45:12 -0800
+Subject: tools: fix cross-compile var clobbering
+
+From: Martin Kelly <martin@martingkelly.com>
+
+commit 7ed1c1901fe52e6c5828deb155920b44b0adabb1 upstream.
+
+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>
+Cc: Ignat Korchagin <ignat@cloudflare.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ tools/cgroup/Makefile | 1 -
+ tools/gpio/Makefile | 2 --
+ tools/hv/Makefile | 1 -
+ tools/iio/Makefile | 2 --
+ tools/laptop/freefall/Makefile | 1 -
+ tools/leds/Makefile | 1 -
+ tools/perf/Makefile.perf | 6 ------
+ tools/power/acpi/Makefile.config | 3 ---
+ tools/scripts/Makefile.include | 18 ++++++++++++++++++
+ tools/spi/Makefile | 2 --
+ tools/usb/Makefile | 1 -
+ tools/vm/Makefile | 1 -
+ 12 files changed, 18 insertions(+), 21 deletions(-)
+
+--- a/tools/cgroup/Makefile
++++ b/tools/cgroup/Makefile
+@@ -1,7 +1,6 @@
+ # SPDX-License-Identifier: GPL-2.0
+ # Makefile for cgroup tools
+
+-CC = $(CROSS_COMPILE)gcc
+ CFLAGS = -Wall -Wextra
+
+ all: cgroup_event_listener
+--- a/tools/gpio/Makefile
++++ b/tools/gpio/Makefile
+@@ -12,8 +12,6 @@ endif
+ # (this improves performance and avoids hard-to-debug behaviour);
+ MAKEFLAGS += -r
+
+-CC = $(CROSS_COMPILE)gcc
+-LD = $(CROSS_COMPILE)ld
+ CFLAGS += -O2 -Wall -g -D_GNU_SOURCE -I$(OUTPUT)include
+
+ ALL_TARGETS := lsgpio gpio-hammer gpio-event-mon
+--- a/tools/hv/Makefile
++++ b/tools/hv/Makefile
+@@ -1,7 +1,6 @@
+ # SPDX-License-Identifier: GPL-2.0
+ # Makefile for Hyper-V tools
+
+-CC = $(CROSS_COMPILE)gcc
+ WARNINGS = -Wall -Wextra
+ CFLAGS = $(WARNINGS) -g $(shell getconf LFS_CFLAGS)
+
+--- a/tools/iio/Makefile
++++ b/tools/iio/Makefile
+@@ -12,8 +12,6 @@ endif
+ # (this improves performance and avoids hard-to-debug behaviour);
+ MAKEFLAGS += -r
+
+-CC = $(CROSS_COMPILE)gcc
+-LD = $(CROSS_COMPILE)ld
+ CFLAGS += -O2 -Wall -g -D_GNU_SOURCE -I$(OUTPUT)include
+
+ ALL_TARGETS := iio_event_monitor lsiio iio_generic_buffer
+--- a/tools/laptop/freefall/Makefile
++++ b/tools/laptop/freefall/Makefile
+@@ -2,7 +2,6 @@
+ PREFIX ?= /usr
+ SBINDIR ?= sbin
+ INSTALL ?= install
+-CC = $(CROSS_COMPILE)gcc
+
+ TARGET = freefall
+
+--- a/tools/leds/Makefile
++++ b/tools/leds/Makefile
+@@ -1,7 +1,6 @@
+ # SPDX-License-Identifier: GPL-2.0
+ # Makefile for LEDs tools
+
+-CC = $(CROSS_COMPILE)gcc
+ CFLAGS = -Wall -Wextra -g -I../../include/uapi
+
+ all: uledmon led_hw_brightness_mon
+--- a/tools/perf/Makefile.perf
++++ b/tools/perf/Makefile.perf
+@@ -144,12 +144,6 @@ define allow-override
+ $(eval $(1) = $(2)))
+ endef
+
+-# Allow setting CC and AR and LD, or setting CROSS_COMPILE as a prefix.
+-$(call allow-override,CC,$(CROSS_COMPILE)gcc)
+-$(call allow-override,AR,$(CROSS_COMPILE)ar)
+-$(call allow-override,LD,$(CROSS_COMPILE)ld)
+-$(call allow-override,CXX,$(CROSS_COMPILE)g++)
+-
+ LD += $(EXTRA_LDFLAGS)
+
+ HOSTCC ?= gcc
+--- a/tools/power/acpi/Makefile.config
++++ b/tools/power/acpi/Makefile.config
+@@ -56,9 +56,6 @@ INSTALL_SCRIPT = ${INSTALL_PROGRAM}
+ # to compile vs uClibc, that can be done here as well.
+ CROSS = #/usr/i386-linux-uclibc/usr/bin/i386-uclibc-
+ CROSS_COMPILE ?= $(CROSS)
+-CC = $(CROSS_COMPILE)gcc
+-LD = $(CROSS_COMPILE)gcc
+-STRIP = $(CROSS_COMPILE)strip
+ HOSTCC = gcc
+
+ # check if compiler option is supported
+--- a/tools/scripts/Makefile.include
++++ b/tools/scripts/Makefile.include
+@@ -42,6 +42,24 @@ EXTRA_WARNINGS += -Wformat
+
+ CC_NO_CLANG := $(shell $(CC) -dM -E -x c /dev/null | grep -Fq "__clang__"; echo $$?)
+
++# Makefiles suck: This macro sets a default value of $(2) for the
++# variable named by $(1), unless the variable has been set by
++# environment or command line. This is necessary for CC and AR
++# because make sets default values, so the simpler ?= approach
++# won't work as expected.
++define allow-override
++ $(if $(or $(findstring environment,$(origin $(1))),\
++ $(findstring command line,$(origin $(1)))),,\
++ $(eval $(1) = $(2)))
++endef
++
++# Allow setting various cross-compile vars or setting CROSS_COMPILE as a prefix.
++$(call allow-override,CC,$(CROSS_COMPILE)gcc)
++$(call allow-override,AR,$(CROSS_COMPILE)ar)
++$(call allow-override,LD,$(CROSS_COMPILE)ld)
++$(call allow-override,CXX,$(CROSS_COMPILE)g++)
++$(call allow-override,STRIP,$(CROSS_COMPILE)strip)
++
+ ifeq ($(CC_NO_CLANG), 1)
+ EXTRA_WARNINGS += -Wstrict-aliasing=3
+ endif
+--- a/tools/spi/Makefile
++++ b/tools/spi/Makefile
+@@ -11,8 +11,6 @@ endif
+ # (this improves performance and avoids hard-to-debug behaviour);
+ MAKEFLAGS += -r
+
+-CC = $(CROSS_COMPILE)gcc
+-LD = $(CROSS_COMPILE)ld
+ CFLAGS += -O2 -Wall -g -D_GNU_SOURCE -I$(OUTPUT)include
+
+ ALL_TARGETS := spidev_test spidev_fdx
+--- a/tools/usb/Makefile
++++ b/tools/usb/Makefile
+@@ -1,7 +1,6 @@
+ # SPDX-License-Identifier: GPL-2.0
+ # Makefile for USB tools
+
+-CC = $(CROSS_COMPILE)gcc
+ PTHREAD_LIBS = -lpthread
+ WARNINGS = -Wall -Wextra
+ CFLAGS = $(WARNINGS) -g -I../include
+--- a/tools/vm/Makefile
++++ b/tools/vm/Makefile
+@@ -6,7 +6,6 @@ TARGETS=page-types slabinfo page_owner_s
+ LIB_DIR = ../lib/api
+ LIBS = $(LIB_DIR)/libapi.a
+
+-CC = $(CROSS_COMPILE)gcc
+ CFLAGS = -Wall -Wextra -I../lib/
+ LDFLAGS = $(LIBS)
+
projects / thirdparty / kernel / stable-queue.git / commitdiff
