| # ========================================================================== |
| # 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 $(CONFIG_LFS),-D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64) \ |
| -D"BB_VER=KBUILD_STR($(BB_VER))" |
| |
| 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) |
| |
| CFLAGS += $(call cc-option,-fno-builtin-strlen -finline-limit=0 -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 -static-libgcc,) |
| CFLAGS += $(call cc-option,-falign-functions=1 -falign-jumps=1 -falign-labels=1 -falign-loops=1,) |
| # 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,) |
| |
| # 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 += $(call cc-option,-Os,$(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 += $(call cc-option,-Os,$(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 |
| |
| # 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;}' >crypttest.c; $(CC) $(CFLAGS) -lcrypt -o /dev/null crypttest.c >/dev/null 2>&1 && echo "y"; rm crypttest.c) |
| ifeq ($(CRYPT_AVAILABLE),y) |
| LDLIBS += m crypt |
| else |
| LDLIBS += m |
| 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_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 |
| |
| ifneq ($(CONFIG_EXTRA_LDLIBS),) |
| LDLIBS += $(strip $(subst ",,$(CONFIG_EXTRA_LDLIBS))) |
| #")) |
| 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 |
