Merge remote-tracking branch 'kbuild/for-next'

[karo-tx-linux.git] / Makefile

diff --git a/Makefile b/Makefile
index d5b37391195f80866ad2b831a417039b3ee230cf..5e5c2def19ddb3db004cc8f264df78fb5b71764e 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -342,9 +342,14 @@ include scripts/Kbuild.include
 # Make variables (CC, etc...)
 AS             = $(CROSS_COMPILE)as
 LD             = $(CROSS_COMPILE)ld
+LDFINAL        = $(LD)
 CC             = $(CROSS_COMPILE)gcc
 CPP            = $(CC) -E
+ifdef CONFIG_LTO
+AR             = $(CROSS_COMPILE)gcc-ar
+else
 AR             = $(CROSS_COMPILE)ar
+endif
 NM             = $(CROSS_COMPILE)nm
 STRIP          = $(CROSS_COMPILE)strip
 OBJCOPY                = $(CROSS_COMPILE)objcopy
@@ -406,7 +411,7 @@ KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(S
 
 export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION
 export ARCH SRCARCH CONFIG_SHELL HOSTCC HOSTCFLAGS CROSS_COMPILE AS LD CC
-export CPP AR NM STRIP OBJCOPY OBJDUMP
+export CPP AR NM STRIP OBJCOPY OBJDUMP LDFINAL
 export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
 export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
 
@@ -417,6 +422,17 @@ export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
 export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
 export KBUILD_ARFLAGS
 
+ifdef CONFIG_LTO
+# LTO gcc creates a lot of files in TMPDIR, and with /tmp as tmpfs
+# it's easy to drive the machine OOM. Use the object directory
+# instead.
+ifndef TMPDIR
+TMPDIR ?= $(objtree)
+export TMPDIR
+$(info setting TMPDIR=$(objtree) for LTO build)
+endif
+endif
+
 # When compiling out-of-tree modules, put MODVERDIR in the module
 # tree rather than in the kernel tree. The kernel tree might
 # even be read-only.
@@ -777,6 +793,7 @@ endif
 
 include scripts/Makefile.kasan
 include scripts/Makefile.extrawarn
+include scripts/Makefile.lto
 
 # Add any arch overrides and user supplied CPPFLAGS, AFLAGS and CFLAGS as the
 # last assignments
@@ -1075,6 +1092,9 @@ PHONY += kselftest
 kselftest:
        $(Q)$(MAKE) -C tools/testing/selftests run_tests
 
+kselftest-clean:
+       $(Q)$(MAKE) -C tools/testing/selftests clean
+
 # ---------------------------------------------------------------------------
 # Modules
 
@@ -1282,6 +1302,7 @@ help:
        @echo  '  kselftest       - Build and run kernel selftest (run as root)'
        @echo  '                    Build, install, and boot kernel before'
        @echo  '                    running kselftest on it'
+       @echo  '  kselftest-clean - Remove all generated kselftest files'
        @echo  ''
        @echo  'Kernel packaging:'
        @$(MAKE) $(build)=$(package-dir) help