mirror of
https://git.busybox.net/busybox.git
synced 2024-11-23 05:33:33 +08:00
87c31609f4
Extend the changes introduced by commit b4ef2e3467 (Makefile.flags:
suppress some clang-9 warnings) so they also cover the case where
clang is used as a cross-compiler.
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
224 lines
8.0 KiB
Makefile
224 lines
8.0 KiB
Makefile
# ==========================================================================
|
|
# Build system
|
|
# ==========================================================================
|
|
|
|
BB_VER = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)
|
|
export BB_VER
|
|
SKIP_STRIP ?= n
|
|
|
|
# -std=gnu99 needed for [U]LLONG_MAX on some systems
|
|
CPPFLAGS += $(call cc-option,-std=gnu99,)
|
|
|
|
CPPFLAGS += \
|
|
-Iinclude -Ilibbb \
|
|
$(if $(KBUILD_SRC),-Iinclude2 -I$(srctree)/include -I$(srctree)/libbb) \
|
|
-include include/autoconf.h \
|
|
-D_GNU_SOURCE -DNDEBUG \
|
|
$(if $(CONFIG_LFS),-D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64) \
|
|
$(if $(CONFIG_TIME64),-D_TIME_BITS=64) \
|
|
-DBB_VER=$(squote)$(quote)$(BB_VER)$(quote)$(squote)
|
|
|
|
CFLAGS += $(call cc-option,-Wall,)
|
|
CFLAGS += $(call cc-option,-Wshadow,)
|
|
CFLAGS += $(call cc-option,-Wwrite-strings,)
|
|
CFLAGS += $(call cc-option,-Wundef,)
|
|
CFLAGS += $(call cc-option,-Wstrict-prototypes,)
|
|
CFLAGS += $(call cc-option,-Wunused -Wunused-parameter,)
|
|
CFLAGS += $(call cc-option,-Wunused-function -Wunused-value,)
|
|
CFLAGS += $(call cc-option,-Wmissing-prototypes -Wmissing-declarations,)
|
|
CFLAGS += $(call cc-option,-Wno-format-security,)
|
|
# warn about C99 declaration after statement
|
|
CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
|
|
# If you want to add more -Wsomething above, make sure that it is
|
|
# still possible to build bbox without warnings.
|
|
|
|
ifeq ($(CONFIG_WERROR),y)
|
|
CFLAGS += $(call cc-option,-Werror,)
|
|
## TODO:
|
|
## gcc version 4.4.0 20090506 (Red Hat 4.4.0-4) (GCC) is a PITA:
|
|
## const char *ptr; ... off_t v = *(off_t*)ptr; -> BOOM
|
|
## and no easy way to convince it to shut the hell up.
|
|
## We have a lot of such things all over the place.
|
|
## Classic *(off_t*)(void*)ptr does not work,
|
|
## and I am unwilling to do crazy gcc specific ({ void *ppp = ...; })
|
|
## stuff in macros. This would obfuscate the code too much.
|
|
## Maybe try __attribute__((__may_alias__))?
|
|
#CFLAGS += $(call cc-ifversion, -eq, 0404, -fno-strict-aliasing)
|
|
endif
|
|
# gcc 3.x emits bogus "old style proto" warning on find.c:alloc_action()
|
|
CFLAGS += $(call cc-ifversion, -ge, 0400, -Wold-style-definition)
|
|
|
|
ifneq ($(lastword $(subst -, ,$(CC))),clang)
|
|
# "clang-9: warning: optimization flag '-finline-limit=0' is not supported
|
|
CFLAGS += $(call cc-option,-finline-limit=0,)
|
|
endif
|
|
|
|
CFLAGS += $(call cc-option,-fno-builtin-strlen -fomit-frame-pointer -ffunction-sections -fdata-sections,)
|
|
# -fno-guess-branch-probability: prohibit pseudo-random guessing
|
|
# of branch probabilities (hopefully makes bloatcheck more stable):
|
|
CFLAGS += $(call cc-option,-fno-guess-branch-probability,)
|
|
CFLAGS += $(call cc-option,-funsigned-char,)
|
|
|
|
ifeq ($(CONFIG_STATIC_LIBGCC),y)
|
|
# Disable it, for example, if you get
|
|
# "clang-9: warning: argument unused during compilation: '-static-libgcc'"
|
|
CFLAGS += $(call cc-option,-static-libgcc,)
|
|
endif
|
|
|
|
CFLAGS += $(call cc-option,-falign-functions=1,)
|
|
ifneq ($(lastword $(subst -, ,$(CC))),clang)
|
|
# "clang-9: warning: optimization flag '-falign-jumps=1' is not supported" (and same for other two)
|
|
CFLAGS += $(call cc-option,-falign-jumps=1 -falign-labels=1 -falign-loops=1,)
|
|
endif
|
|
|
|
# Defeat .eh_frame bloat (gcc 4.6.3 x86-32 defconfig: 20% smaller busybox binary):
|
|
CFLAGS += $(call cc-option,-fno-unwind-tables,)
|
|
CFLAGS += $(call cc-option,-fno-asynchronous-unwind-tables,)
|
|
# No automatic printf->puts,putchar conversions
|
|
# (try disabling this and comparing assembly, it's instructive)
|
|
CFLAGS += $(call cc-option,-fno-builtin-printf,)
|
|
|
|
# clang-9 does not like "str" + N and "if (CONFIG_ITEM && cond)" constructs
|
|
ifeq ($(lastword $(subst -, ,$(CC))),clang)
|
|
CFLAGS += $(call cc-option,-Wno-string-plus-int -Wno-constant-logical-operand)
|
|
endif
|
|
|
|
# FIXME: These warnings are at least partially to be concerned about and should
|
|
# be fixed..
|
|
#CFLAGS += $(call cc-option,-Wconversion,)
|
|
|
|
ifneq ($(CONFIG_DEBUG),y)
|
|
CFLAGS += $(call cc-option,-Oz,$(call cc-option,-Os,$(call cc-option,-O2,)))
|
|
else
|
|
CFLAGS += $(call cc-option,-g,)
|
|
#CFLAGS += "-D_FORTIFY_SOURCE=2"
|
|
ifeq ($(CONFIG_DEBUG_PESSIMIZE),y)
|
|
CFLAGS += $(call cc-option,-O0,)
|
|
else
|
|
CFLAGS += $(call cc-option,-Oz,$(call cc-option,-Os,$(call cc-option,-O2,)))
|
|
endif
|
|
endif
|
|
ifeq ($(CONFIG_DEBUG_SANITIZE),y)
|
|
CFLAGS += $(call cc-option,-fsanitize=address,)
|
|
CFLAGS += $(call cc-option,-fsanitize=leak,)
|
|
CFLAGS += $(call cc-option,-fsanitize=undefined,)
|
|
endif
|
|
|
|
# If arch/$(ARCH)/Makefile did not override it (with, say, -fPIC)...
|
|
ARCH_FPIC ?= -fpic
|
|
ARCH_FPIE ?= -fpie
|
|
ARCH_PIE ?= -pie
|
|
|
|
# Usage: $(eval $(call pkg_check_modules,VARIABLE-PREFIX,MODULES))
|
|
define pkg_check_modules
|
|
$(1)_CFLAGS := $(shell $(PKG_CONFIG) $(PKG_CONFIG_FLAGS) --cflags $(2))
|
|
$(1)_LIBS := $(shell $(PKG_CONFIG) $(PKG_CONFIG_FLAGS) --libs $(2))
|
|
endef
|
|
|
|
ifeq ($(CONFIG_BUILD_LIBBUSYBOX),y)
|
|
# on i386: 14% smaller libbusybox.so
|
|
# (code itself is 9% bigger, we save on relocs/PLT/GOT)
|
|
CFLAGS += $(ARCH_FPIC)
|
|
# and another 4% reduction of libbusybox.so:
|
|
# (external entry points must be marked EXTERNALLY_VISIBLE)
|
|
CFLAGS += $(call cc-option,-fvisibility=hidden)
|
|
endif
|
|
|
|
ifeq ($(CONFIG_STATIC),y)
|
|
CFLAGS_busybox += -static
|
|
PKG_CONFIG_FLAGS += --static
|
|
endif
|
|
|
|
ifeq ($(CONFIG_PIE),y)
|
|
CFLAGS_busybox += $(ARCH_PIE)
|
|
CFLAGS += $(ARCH_FPIE)
|
|
endif
|
|
|
|
ifneq ($(CONFIG_EXTRA_CFLAGS),)
|
|
CFLAGS += $(strip $(subst ",,$(CONFIG_EXTRA_CFLAGS)))
|
|
#"))
|
|
endif
|
|
|
|
# Note: both "" (string consisting of two quote chars) and empty string
|
|
# are possible, and should be skipped below.
|
|
ifneq ($(subst "",,$(CONFIG_SYSROOT)),)
|
|
CFLAGS += --sysroot=$(CONFIG_SYSROOT)
|
|
export SYSROOT=$(CONFIG_SYSROOT)
|
|
endif
|
|
|
|
# libm may be needed for dc, awk, ntpd
|
|
LDLIBS += m
|
|
# Android has no separate crypt library
|
|
# gcc-4.2.1 fails if we try to feed C source on stdin:
|
|
# echo 'int main(void){return 0;}' | $(CC) $(CFLAGS) -lcrypt -o /dev/null -xc -
|
|
# fall back to using a temp file:
|
|
CRYPT_AVAILABLE := $(shell echo 'int main(void){return 0;}' >bb_libtest.c; $(CC) $(CFLAGS) $(CFLAGS_busybox) -lcrypt -o /dev/null bb_libtest.c >/dev/null 2>&1 && echo "y"; rm bb_libtest.c)
|
|
RT_AVAILABLE := $(shell echo 'int main(void){return 0;}' >bb_libtest.c; $(CC) $(CFLAGS) $(CFLAGS_busybox) -lrt -o /dev/null bb_libtest.c >/dev/null 2>&1 && echo "y"; rm bb_libtest.c)
|
|
ifeq ($(CRYPT_AVAILABLE),y)
|
|
LDLIBS += crypt
|
|
endif
|
|
# librt may be needed for clock_gettime()
|
|
ifeq ($(RT_AVAILABLE),y)
|
|
LDLIBS += rt
|
|
endif
|
|
|
|
# libpam may use libpthread, libdl and/or libaudit.
|
|
# On some platforms that requires an explicit -lpthread, -ldl, -laudit.
|
|
# However, on *other platforms* it fails when some of those flags
|
|
# given needlessly. On some systems, crypt needs pthread.
|
|
#
|
|
# I even had a system where a runtime test for pthread
|
|
# (similar to CRYPT_AVAILABLE test above) was not reliable.
|
|
#
|
|
# Do not propagate this mess by adding libraries to CONFIG_PAM/CRYPT_AVAILABLE blocks.
|
|
# Add libraries you need to CONFIG_EXTRA_LDLIBS instead.
|
|
|
|
ifeq ($(CONFIG_PAM),y)
|
|
LDLIBS += pam pam_misc
|
|
endif
|
|
|
|
ifeq ($(CONFIG_SELINUX),y)
|
|
SELINUX_PC_MODULES = libselinux libsepol
|
|
$(eval $(call pkg_check_modules,SELINUX,$(SELINUX_PC_MODULES)))
|
|
CPPFLAGS += $(SELINUX_CFLAGS)
|
|
LDLIBS += $(if $(SELINUX_LIBS),$(SELINUX_LIBS:-l%=%),$(SELINUX_PC_MODULES:lib%=%))
|
|
endif
|
|
|
|
ifeq ($(CONFIG_FEATURE_NSLOOKUP_BIG),y)
|
|
ifneq (,$(findstring linux,$(shell $(CC) $(CFLAGS) -dumpmachine)))
|
|
LDLIBS += resolv
|
|
endif
|
|
ifneq (,$(findstring gnu,$(shell $(CC) $(CFLAGS) -dumpmachine)))
|
|
LDLIBS += resolv
|
|
endif
|
|
endif
|
|
|
|
ifeq ($(CONFIG_EFENCE),y)
|
|
LDLIBS += efence
|
|
endif
|
|
|
|
ifeq ($(CONFIG_DMALLOC),y)
|
|
LDLIBS += dmalloc
|
|
endif
|
|
|
|
# If a flat binary should be built, CFLAGS_busybox="-elf2flt"
|
|
# env var should be set for make invocation.
|
|
# Here we check whether CFLAGS_busybox indeed contains that flag.
|
|
# (For historical reasons, we also check LDFLAGS, which doesn't
|
|
# seem to be entirely correct variable to put "-elf2flt" into).
|
|
W_ELF2FLT = -elf2flt
|
|
ifneq (,$(findstring $(W_ELF2FLT),$(LDFLAGS) $(CFLAGS_busybox)))
|
|
SKIP_STRIP = y
|
|
endif
|
|
|
|
ifneq ($(CONFIG_EXTRA_LDFLAGS),)
|
|
LDFLAGS += $(strip $(subst ",,$(CONFIG_EXTRA_LDFLAGS)))
|
|
#"))
|
|
endif
|
|
|
|
# Busybox is a stack-fatty so make sure we increase default size
|
|
# TODO: use "make stksizes" to find & fix big stack users
|
|
# (we stole scripts/checkstack.pl from the kernel... thanks guys!)
|
|
# Reduced from 20k to 16k in 1.9.0.
|
|
FLTFLAGS += -s 16000
|