linux_dsm_epyc7002/tools/scripts/Makefile.include
Yonghong Song 475312897e tools: Allow proper CC/CXX/... override with LLVM=1 in Makefile.include
commit f62700ce63a315b4607cc9e97aa15ea409a677b9 upstream.

selftests/bpf/Makefile includes tools/scripts/Makefile.include.
With the following command
  make -j60 LLVM=1 LLVM_IAS=1  <=== compile kernel
  make -j60 -C tools/testing/selftests/bpf LLVM=1 LLVM_IAS=1 V=1
some files are still compiled with gcc. This patch
fixed the case if CC/AR/LD/CXX/STRIP is allowed to be
overridden, it will be written to clang/llvm-ar/..., instead of
gcc binaries. The definition of CC_NO_CLANG is also relocated
to the place after the above CC is defined.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210413153419.3028165-1-yhs@fb.com
Cc: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-31 08:16:10 +02:00

151 lines
4.5 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
ifneq ($(O),)
ifeq ($(origin O), command line)
dummy := $(if $(shell cd $(PWD); test -d $(O) || echo $(O)),$(error O=$(O) does not exist),)
ABSOLUTE_O := $(shell cd $(PWD); cd $(O) ; pwd)
OUTPUT := $(ABSOLUTE_O)/$(if $(subdir),$(subdir)/)
COMMAND_O := O=$(ABSOLUTE_O)
ifeq ($(objtree),)
objtree := $(O)
endif
endif
endif
# check that the output directory actually exists
ifneq ($(OUTPUT),)
OUTDIR := $(shell cd $(OUTPUT) && pwd)
$(if $(OUTDIR),, $(error output directory "$(OUTPUT)" does not exist))
endif
#
# Include saner warnings here, which can catch bugs:
#
EXTRA_WARNINGS := -Wbad-function-cast
EXTRA_WARNINGS += -Wdeclaration-after-statement
EXTRA_WARNINGS += -Wformat-security
EXTRA_WARNINGS += -Wformat-y2k
EXTRA_WARNINGS += -Winit-self
EXTRA_WARNINGS += -Wmissing-declarations
EXTRA_WARNINGS += -Wmissing-prototypes
EXTRA_WARNINGS += -Wnested-externs
EXTRA_WARNINGS += -Wno-system-headers
EXTRA_WARNINGS += -Wold-style-definition
EXTRA_WARNINGS += -Wpacked
EXTRA_WARNINGS += -Wredundant-decls
EXTRA_WARNINGS += -Wstrict-prototypes
EXTRA_WARNINGS += -Wswitch-default
EXTRA_WARNINGS += -Wswitch-enum
EXTRA_WARNINGS += -Wundef
EXTRA_WARNINGS += -Wwrite-strings
EXTRA_WARNINGS += -Wformat
# 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) = $(2)))
endef
ifneq ($(LLVM),)
$(call allow-override,CC,clang)
$(call allow-override,AR,llvm-ar)
$(call allow-override,LD,ld.lld)
$(call allow-override,CXX,clang++)
$(call allow-override,STRIP,llvm-strip)
else
# 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)
endif
CC_NO_CLANG := $(shell $(CC) -dM -E -x c /dev/null | grep -Fq "__clang__"; echo $$?)
ifneq ($(LLVM),)
HOSTAR ?= llvm-ar
HOSTCC ?= clang
HOSTLD ?= ld.lld
else
HOSTAR ?= ar
HOSTCC ?= gcc
HOSTLD ?= ld
endif
ifeq ($(CC_NO_CLANG), 1)
EXTRA_WARNINGS += -Wstrict-aliasing=3
endif
# Hack to avoid type-punned warnings on old systems such as RHEL5:
# We should be changing CFLAGS and checking gcc version, but this
# will do for now and keep the above -Wstrict-aliasing=3 in place
# in newer systems.
# Needed for the __raw_cmpxchg in tools/arch/x86/include/asm/cmpxchg.h
#
# See https://lkml.org/lkml/2006/11/28/253 and https://gcc.gnu.org/gcc-4.8/changes.html,
# that takes into account Linus's comments (search for Wshadow) for the reasoning about
# -Wshadow not being interesting before gcc 4.8.
ifneq ($(filter 3.%,$(MAKE_VERSION)),) # make-3
EXTRA_WARNINGS += -fno-strict-aliasing
EXTRA_WARNINGS += -Wno-shadow
else
EXTRA_WARNINGS += -Wshadow
endif
ifneq ($(findstring $(MAKEFLAGS), w),w)
PRINT_DIR = --no-print-directory
else
NO_SUBDIR = :
endif
ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
silent=1
endif
#
# Define a callable command for descending to a new directory
#
# Call by doing: $(call descend,directory[,target])
#
descend = \
+mkdir -p $(OUTPUT)$(1) && \
$(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2)
QUIET_SUBDIR0 = +$(MAKE) $(COMMAND_O) -C # space to separate -C and subdir
QUIET_SUBDIR1 =
ifneq ($(silent),1)
ifneq ($(V),1)
QUIET_CC = @echo ' CC '$@;
QUIET_CC_FPIC = @echo ' CC FPIC '$@;
QUIET_CLANG = @echo ' CLANG '$@;
QUIET_AR = @echo ' AR '$@;
QUIET_LINK = @echo ' LINK '$@;
QUIET_MKDIR = @echo ' MKDIR '$@;
QUIET_GEN = @echo ' GEN '$@;
QUIET_SUBDIR0 = +@subdir=
QUIET_SUBDIR1 = ;$(NO_SUBDIR) \
echo ' SUBDIR '$$subdir; \
$(MAKE) $(PRINT_DIR) -C $$subdir
QUIET_FLEX = @echo ' FLEX '$@;
QUIET_BISON = @echo ' BISON '$@;
descend = \
+@echo ' DESCEND '$(1); \
mkdir -p $(OUTPUT)$(1) && \
$(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2)
QUIET_CLEAN = @printf ' CLEAN %s\n' $1;
QUIET_INSTALL = @printf ' INSTALL %s\n' $1;
QUIET_UNINST = @printf ' UNINST %s\n' $1;
endif
endif
pound := \#