linux/tools/scripts/Makefile.include
Sedat Dilek 211a741cd3 tools: Factor Clang, LLC and LLVM utils definitions
When dealing with BPF/BTF/pahole and DWARF v5 I wanted to build bpftool.

While looking into the source code I found duplicate assignments in misc tools
for the LLVM eco system, e.g. clang and llvm-objcopy.

Move the Clang, LLC and/or LLVM utils definitions to tools/scripts/Makefile.include
file and add missing includes where needed. Honestly, I was inspired by the commit
c8a950d0d3 ("tools: Factor HOSTCC, HOSTLD, HOSTAR definitions").

I tested with bpftool and perf on Debian/testing AMD64 and LLVM/Clang v11.1.0-rc1.

Build instructions:

[ make and make-options ]
MAKE="make V=1"
MAKE_OPTS="HOSTCC=clang HOSTCXX=clang++ HOSTLD=ld.lld CC=clang LD=ld.lld LLVM=1 LLVM_IAS=1"
MAKE_OPTS="$MAKE_OPTS PAHOLE=/opt/pahole/bin/pahole"

[ clean-up ]
$MAKE $MAKE_OPTS -C tools/ clean

[ bpftool ]
$MAKE $MAKE_OPTS -C tools/bpf/bpftool/

[ perf ]
PYTHON=python3 $MAKE $MAKE_OPTS -C tools/perf/

I was careful with respecting the user's wish to override custom compiler, linker,
GNU/binutils and/or LLVM utils settings.

Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com> # tools/build and tools/perf
Link: https://lore.kernel.org/bpf/20210128015117.20515-1-sedat.dilek@gmail.com
2021-01-29 01:25:34 +01:00

150 lines
4.4 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
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)
ifneq ($(LLVM),)
HOSTAR ?= llvm-ar
HOSTCC ?= clang
HOSTLD ?= ld.lld
else
HOSTAR ?= ar
HOSTCC ?= gcc
HOSTLD ?= ld
endif
# Some tools require Clang, LLC and/or LLVM utils
CLANG ?= clang
LLC ?= llc
LLVM_CONFIG ?= llvm-config
LLVM_OBJCOPY ?= llvm-objcopy
LLVM_STRIP ?= llvm-strip
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 := \#