linux/tools/scripts/Makefile.include
Masahiro Yamada 6f0fa58e45 kbuild: simplify silent build (-s) detection
This allows to detect -s (--silent) option without checking GNU Make
version.

As commit e36aaea289 ("kbuild: Fix silent builds with make-4")
pointed out, GNU Make 4.x changed the way/order it presents the
command line options into MAKEFLAGS.

In Make 3.8x, 's' is always the first in a group of short options.
The group may be prefixed with '-' in some cases.

In Make 4.x, 's' is always the last in a group of short options.

As commit e6ac89fabd ("kbuild: Correctly deal with make options
which contain an 's'") addressed, we also need to deal with long
options that contain 's', like --warn-undefined-variables.

Test cases:

[1] command line input:    make --silent
     -> MAKEFLAGS for Make 3.8x:    s
     -> MAKEFLAGS for Make 4.x :    s

[2] command line input:    make -srR
     -> MAKEFLAGS for Make 3.8x:    sRr
     -> MAKEFLAGS for Make 4.x :    rRs

[3] command line input:    make -s -rR --warn-undefined-variables
     -> MAKEFLAGS for Make 3.8x:    --warn-undefined-variables -sRr
     -> MAKEFLAGS for Make 4.x :    rRs --warn-undefined-variables

My idea to cater to all the cases more easily is to filter out long
options (--%), then search 's' with $(findstring ...).  This way will
be more future-proof even if future versions of Make put 's' in the
middle of the group.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-06-06 09:01:12 +09:00

101 lines
2.9 KiB
Makefile

ifneq ($(O),)
ifeq ($(origin O), command line)
dummy := $(if $(shell test -d $(O) || echo $(O)),$(error O=$(O) does not exist),)
ABSOLUTE_O := $(shell 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) && /bin/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 += -Wshadow
EXTRA_WARNINGS += -Wstrict-prototypes
EXTRA_WARNINGS += -Wswitch-default
EXTRA_WARNINGS += -Wswitch-enum
EXTRA_WARNINGS += -Wundef
EXTRA_WARNINGS += -Wwrite-strings
EXTRA_WARNINGS += -Wformat
ifneq ($(CC), clang)
EXTRA_WARNINGS += -Wstrict-aliasing=3
endif
# Hack to avoid type-punned warnings on old systems such as RHEL5:
# We should be changing CFLAGS and checking gcc version, but this
# will do for now and keep the above -Wstrict-aliasing=3 in place
# in newer systems.
# Needed for the __raw_cmpxchg in tools/arch/x86/include/asm/cmpxchg.h
ifneq ($(filter 3.%,$(MAKE_VERSION)),) # make-3
EXTRA_WARNINGS += -fno-strict-aliasing
endif
ifneq ($(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 '$@;
QUIET_AR = @echo ' AR '$@;
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;
endif
endif