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Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek: - GCC plugin support by Emese Revfy from grsecurity, with a fixup from Kees Cook. The plugins are meant to be used for static analysis of the kernel code. Two plugins are provided already. - reduction of the gcc commandline by Arnd Bergmann. - IS_ENABLED / IS_REACHABLE macro enhancements by Masahiro Yamada - bin2c fix by Michael Tautschnig - setlocalversion fix by Wolfram Sang * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: gcc-plugins: disable under COMPILE_TEST kbuild: Abort build on bad stack protector flag scripts: Fix size mismatch of kexec_purgatory_size kbuild: make samples depend on headers_install Kbuild: don't add obj tree in additional includes Kbuild: arch: look for generated headers in obtree Kbuild: always prefix objtree in LINUXINCLUDE Kbuild: avoid duplicate include path Kbuild: don't add ../../ to include path vmlinux.lds.h: replace config_enabled() with IS_ENABLED() kconfig.h: allow to use IS_{ENABLE,REACHABLE} in macro expansion kconfig.h: use already defined macros for IS_REACHABLE() define export.h: use __is_defined() to check if __KSYM_* is defined kconfig.h: use __is_defined() to check if MODULE is defined kbuild: setlocalversion: print error to STDERR Add sancov plugin Add Cyclomatic complexity GCC plugin GCC plugin infrastructure Shared library support
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‎.gitignore

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@@ -37,6 +37,7 @@ modules.builtin
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Module.symvers
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*.dwo
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*.su
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*.c.[012]*.*
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#
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# Top-level generic files

‎Documentation/dontdiff

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*.bc
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*.bin
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*.bz2
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*.c.[012]*.*
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*.cis
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*.cpio
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*.csp

‎Documentation/gcc-plugins.txt

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GCC plugin infrastructure
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=========================
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1. Introduction
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===============
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GCC plugins are loadable modules that provide extra features to the
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compiler [1]. They are useful for runtime instrumentation and static analysis.
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We can analyse, change and add further code during compilation via
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callbacks [2], GIMPLE [3], IPA [4] and RTL passes [5].
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The GCC plugin infrastructure of the kernel supports all gcc versions from
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4.5 to 6.0, building out-of-tree modules, cross-compilation and building in a
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separate directory.
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Plugin source files have to be compilable by both a C and a C++ compiler as well
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because gcc versions 4.5 and 4.6 are compiled by a C compiler,
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gcc-4.7 can be compiled by a C or a C++ compiler,
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and versions 4.8+ can only be compiled by a C++ compiler.
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Currently the GCC plugin infrastructure supports only the x86, arm and arm64
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architectures.
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This infrastructure was ported from grsecurity [6] and PaX [7].
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--
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[1] https://gcc.gnu.org/onlinedocs/gccint/Plugins.html
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[2] https://gcc.gnu.org/onlinedocs/gccint/Plugin-API.html#Plugin-API
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[3] https://gcc.gnu.org/onlinedocs/gccint/GIMPLE.html
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[4] https://gcc.gnu.org/onlinedocs/gccint/IPA.html
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[5] https://gcc.gnu.org/onlinedocs/gccint/RTL.html
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[6] https://grsecurity.net/
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[7] https://pax.grsecurity.net/
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2. Files
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========
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$(src)/scripts/gcc-plugins
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This is the directory of the GCC plugins.
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$(src)/scripts/gcc-plugins/gcc-common.h
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This is a compatibility header for GCC plugins.
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It should be always included instead of individual gcc headers.
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$(src)/scripts/gcc-plugin.sh
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This script checks the availability of the included headers in
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gcc-common.h and chooses the proper host compiler to build the plugins
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(gcc-4.7 can be built by either gcc or g++).
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$(src)/scripts/gcc-plugins/gcc-generate-gimple-pass.h
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$(src)/scripts/gcc-plugins/gcc-generate-ipa-pass.h
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$(src)/scripts/gcc-plugins/gcc-generate-simple_ipa-pass.h
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$(src)/scripts/gcc-plugins/gcc-generate-rtl-pass.h
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These headers automatically generate the registration structures for
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GIMPLE, SIMPLE_IPA, IPA and RTL passes. They support all gcc versions
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from 4.5 to 6.0.
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They should be preferred to creating the structures by hand.
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3. Usage
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========
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You must install the gcc plugin headers for your gcc version,
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e.g., on Ubuntu for gcc-4.9:
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apt-get install gcc-4.9-plugin-dev
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Enable a GCC plugin based feature in the kernel config:
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CONFIG_GCC_PLUGIN_CYC_COMPLEXITY = y
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To compile only the plugin(s):
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make gcc-plugins
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or just run the kernel make and compile the whole kernel with
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the cyclomatic complexity GCC plugin.
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4. How to add a new GCC plugin
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==============================
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The GCC plugins are in $(src)/scripts/gcc-plugins/. You can use a file or a directory
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here. It must be added to $(src)/scripts/gcc-plugins/Makefile,
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$(src)/scripts/Makefile.gcc-plugins and $(src)/arch/Kconfig.
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See the cyc_complexity_plugin.c (CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) GCC plugin.

‎MAINTAINERS

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@@ -5094,6 +5094,15 @@ L: linux-scsi@vger.kernel.org
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S: Odd Fixes (e.g., new signatures)
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F: drivers/scsi/fdomain.*
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GCC PLUGINS
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M: Kees Cook <keescook@chromium.org>
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R: Emese Revfy <re.emese@gmail.com>
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L: kernel-hardening@lists.openwall.com
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S: Maintained
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F: scripts/gcc-plugins/
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F: scripts/gcc-plugin.sh
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F: Documentation/gcc-plugins.txt
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GCOV BASED KERNEL PROFILING
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M: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
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S: Maintained

‎Makefile

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@@ -371,26 +371,27 @@ CFLAGS_KERNEL =
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AFLAGS_KERNEL =
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LDFLAGS_vmlinux =
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CFLAGS_GCOV = -fprofile-arcs -ftest-coverage -fno-tree-loop-im
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CFLAGS_KCOV = -fsanitize-coverage=trace-pc
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CFLAGS_KCOV := $(call cc-option,-fsanitize-coverage=trace-pc,)
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# Use USERINCLUDE when you must reference the UAPI directories only.
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USERINCLUDE := \
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-I$(srctree)/arch/$(hdr-arch)/include/uapi \
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-Iarch/$(hdr-arch)/include/generated/uapi \
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-I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
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-I$(srctree)/include/uapi \
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-Iinclude/generated/uapi \
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-I$(objtree)/include/generated/uapi \
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-include $(srctree)/include/linux/kconfig.h
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# Use LINUXINCLUDE when you must reference the include/ directory.
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# Needed to be compatible with the O= option
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LINUXINCLUDE := \
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-I$(srctree)/arch/$(hdr-arch)/include \
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-Iarch/$(hdr-arch)/include/generated/uapi \
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-Iarch/$(hdr-arch)/include/generated \
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-I$(objtree)/arch/$(hdr-arch)/include/generated/uapi \
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-I$(objtree)/arch/$(hdr-arch)/include/generated \
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$(if $(KBUILD_SRC), -I$(srctree)/include) \
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-Iinclude \
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$(USERINCLUDE)
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-I$(objtree)/include
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LINUXINCLUDE += $(filter-out $(LINUXINCLUDE),$(USERINCLUDE))
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KBUILD_CPPFLAGS := -D__KERNEL__
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@@ -554,7 +555,7 @@ ifeq ($(KBUILD_EXTMOD),)
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# in parallel
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PHONY += scripts
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scripts: scripts_basic include/config/auto.conf include/config/tristate.conf \
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asm-generic
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asm-generic gcc-plugins
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$(Q)$(MAKE) $(build)=$(@)
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# Objects we will link into vmlinux / subdirs we need to visit
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# Tell gcc to never replace conditional load with a non-conditional one
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KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0)
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PHONY += gcc-plugins
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gcc-plugins: scripts_basic
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ifdef CONFIG_GCC_PLUGINS
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$(Q)$(MAKE) $(build)=scripts/gcc-plugins
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endif
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@:
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include scripts/Makefile.gcc-plugins
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ifdef CONFIG_READABLE_ASM
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# Disable optimizations that make assembler listings hard to read.
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# reorder blocks reorders the control in the function
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endif
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# Find arch-specific stack protector compiler sanity-checking script.
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ifdef CONFIG_CC_STACKPROTECTOR
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stackp-path := $(srctree)/scripts/gcc-$(ARCH)_$(BITS)-has-stack-protector.sh
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ifneq ($(wildcard $(stackp-path)),)
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stackp-check := $(stackp-path)
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endif
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stackp-path := $(srctree)/scripts/gcc-$(SRCARCH)_$(BITS)-has-stack-protector.sh
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stackp-check := $(wildcard $(stackp-path))
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endif
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KBUILD_CFLAGS += $(stackp-flag)
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ifdef CONFIG_KCOV
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ifeq ($(call cc-option, $(CFLAGS_KCOV)),)
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$(warning Cannot use CONFIG_KCOV: \
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-fsanitize-coverage=trace-pc is not supported by compiler)
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CFLAGS_KCOV =
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endif
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endif
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ifeq ($(cc-name),clang)
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KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
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KBUILD_CPPFLAGS += $(call cc-option,-Wno-unknown-warning-option,)
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archprepare: archheaders archscripts prepare1 scripts_basic
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prepare0: archprepare
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prepare0: archprepare gcc-plugins
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$(Q)$(MAKE) $(build)=.
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# All the preparing..
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-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
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-o -name '*.symtypes' -o -name 'modules.order' \
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-o -name modules.builtin -o -name '.tmp_*.o.*' \
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-o -name '*.c.[012]*.*' \
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-o -name '*.gcno' \) -type f -print | xargs rm -f
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# Generate tags for editors
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$(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \
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$(build)=$(build-dir)
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# Make sure the latest headers are built for Documentation
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Documentation/: headers_install
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Documentation/ samples/: headers_install
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%/: prepare scripts FORCE
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$(cmd_crmodverdir)
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$(Q)$(MAKE) KBUILD_MODULES=$(if $(CONFIG_MODULES),1) \

‎arch/Kconfig

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See Documentation/prctl/seccomp_filter.txt for details.
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config HAVE_GCC_PLUGINS
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bool
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help
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An arch should select this symbol if it supports building with
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GCC plugins.
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menuconfig GCC_PLUGINS
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bool "GCC plugins"
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depends on HAVE_GCC_PLUGINS
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depends on !COMPILE_TEST
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help
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GCC plugins are loadable modules that provide extra features to the
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compiler. They are useful for runtime instrumentation and static analysis.
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See Documentation/gcc-plugins.txt for details.
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config GCC_PLUGIN_CYC_COMPLEXITY
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bool "Compute the cyclomatic complexity of a function"
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depends on GCC_PLUGINS
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help
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The complexity M of a function's control flow graph is defined as:
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M = E - N + 2P
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where
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E = the number of edges
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N = the number of nodes
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P = the number of connected components (exit nodes).
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config GCC_PLUGIN_SANCOV
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bool
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depends on GCC_PLUGINS
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help
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This plugin inserts a __sanitizer_cov_trace_pc() call at the start of
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basic blocks. It supports all gcc versions with plugin support (from
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gcc-4.5 on). It is based on the commit "Add fuzzing coverage support"
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by Dmitry Vyukov <dvyukov@google.com>.
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config HAVE_CC_STACKPROTECTOR
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bool
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help

‎arch/alpha/boot/Makefile

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HOSTCFLAGS := -Wall -I$(objtree)/usr/include
18-
BOOTCFLAGS += -I$(obj) -I$(srctree)/$(obj)
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BOOTCFLAGS += -I$(objtree)/$(obj) -I$(srctree)/$(obj)
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# SRM bootable image. Copy to offset 512 of a partition.
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$(obj)/bootimage: $(addprefix $(obj)/tools/,mkbb lxboot bootlx) $(obj)/vmlinux.nh

‎arch/arm/Kconfig

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select HAVE_FTRACE_MCOUNT_RECORD if (!XIP_KERNEL)
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select HAVE_FUNCTION_GRAPH_TRACER if (!THUMB2_KERNEL)
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select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
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select HAVE_GCC_PLUGINS
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select HAVE_GENERIC_DMA_COHERENT
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select HAVE_HW_BREAKPOINT if (PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7))
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select HAVE_IDE if PCI || ISA || PCMCIA

‎arch/arm64/Kconfig

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select HAVE_FTRACE_MCOUNT_RECORD
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select HAVE_FUNCTION_GRAPH_TRACER
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select HAVE_GCC_PLUGINS
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select HAVE_GENERIC_DMA_COHERENT
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select HAVE_HW_BREAKPOINT if PERF_EVENTS
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select HAVE_IRQ_TIME_ACCOUNTING

‎arch/powerpc/boot/Makefile

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BOOTCFLAGS += -fno-stack-protector
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endif
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46-
BOOTCFLAGS += -I$(obj) -I$(srctree)/$(obj)
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BOOTCFLAGS += -I$(objtree)/$(obj) -I$(srctree)/$(obj)
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4848
DTC_FLAGS ?= -p 1024
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‎arch/powerpc/kvm/Makefile

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obj-$(CONFIG_KVM_EXIT_TIMING) += timing.o
2121
obj-$(CONFIG_KVM_BOOK3S_HANDLER) += book3s_exports.o
2222

23-
AFLAGS_booke_interrupts.o := -I$(obj)
23+
AFLAGS_booke_interrupts.o := -I$(objtree)/$(obj)
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2525
kvm-e500-objs := \
2626
$(common-objs-y) \

‎arch/s390/boot/compressed/Makefile

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$(obj)/sizes.h: vmlinux
3434
$(call if_changed,sizes)
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36-
AFLAGS_head.o += -I$(obj)
36+
AFLAGS_head.o += -I$(objtree)/$(obj)
3737
$(obj)/head.o: $(obj)/sizes.h
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39-
CFLAGS_misc.o += -I$(obj)
39+
CFLAGS_misc.o += -I$(objtree)/$(obj)
4040
$(obj)/misc.o: $(obj)/sizes.h
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4242
OBJCOPYFLAGS_vmlinux.bin := -R .comment -S

‎arch/um/Kconfig.common

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select GENERIC_CPU_DEVICES
1010
select GENERIC_IO
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select GENERIC_CLOCKEVENTS
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select HAVE_GCC_PLUGINS
1213
select TTY # Needed for line.c
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1415
config MMU

‎arch/um/Makefile

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7979
KBUILD_CPPFLAGS += -I$(srctree)/$(HOST_DIR)/include \
8080
-I$(srctree)/$(HOST_DIR)/include/uapi \
81-
-I$(HOST_DIR)/include/generated \
82-
-I$(HOST_DIR)/include/generated/uapi
81+
-I$(objtree)/$(HOST_DIR)/include/generated \
82+
-I$(objtree)/$(HOST_DIR)/include/generated/uapi
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8484
# -Derrno=kernel_errno - This turns all kernel references to errno into
8585
# kernel_errno to separate them from the libc errno. This allows -fno-common

‎arch/x86/Kconfig

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111111
select HAVE_FUNCTION_GRAPH_FP_TEST
112112
select HAVE_FUNCTION_GRAPH_TRACER
113113
select HAVE_FUNCTION_TRACER
114+
select HAVE_GCC_PLUGINS
114115
select HAVE_GENERIC_DMA_COHERENT if X86_32
115116
select HAVE_HW_BREAKPOINT
116117
select HAVE_IDE

‎arch/x86/boot/Makefile

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9696
$(call if_changed,zoffset)
9797

9898

99-
AFLAGS_header.o += -I$(obj)
99+
AFLAGS_header.o += -I$(objtree)/$(obj)
100100
$(obj)/header.o: $(obj)/zoffset.h
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102102
LDFLAGS_setup.elf := -T

‎arch/x86/entry/vdso/Makefile

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@@ -75,7 +75,7 @@ CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \
7575
-fno-omit-frame-pointer -foptimize-sibling-calls \
7676
-DDISABLE_BRANCH_PROFILING -DBUILD_VDSO
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78-
$(vobjs): KBUILD_CFLAGS += $(CFL)
78+
$(vobjs): KBUILD_CFLAGS := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS)) $(CFL)
7979

8080
#
8181
# vDSO code runs in userspace and -pg doesn't help with profiling anyway.
@@ -145,6 +145,7 @@ KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS))
145145
KBUILD_CFLAGS_32 := $(filter-out -mcmodel=kernel,$(KBUILD_CFLAGS_32))
146146
KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32))
147147
KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32))
148+
KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32))
148149
KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic
149150
KBUILD_CFLAGS_32 += $(call cc-option, -fno-stack-protector)
150151
KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls)

‎arch/x86/purgatory/Makefile

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@@ -8,6 +8,8 @@ PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))
88
LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined -nostdlib -z nodefaultlib
99
targets += purgatory.ro
1010

11+
KCOV_INSTRUMENT := n
12+
1113
# Default KBUILD_CFLAGS can have -pg option set when FTRACE is enabled. That
1214
# in turn leaves some undefined symbols like __fentry__ in purgatory and not
1315
# sure how to relocate those. Like kexec-tools, use custom flags.

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