X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=Makefile.flags;h=f3c897b0687f035f2649a292b68f888afcbc7f43;hb=b0648b0e7874e8551df64708532346a049ab7f2c;hp=68dfa57ecff17bc88cdcd55bfa3577e2e6ae4c13;hpb=bf6343796e834183ff1b0c1b9416676e8488afa5;p=oweals%2Fbusybox.git

diff --git a/Makefile.flags b/Makefile.flags
index 68dfa57ec..f3c897b06 100644
--- a/Makefile.flags
+++ b/Makefile.flags
@@ -15,7 +15,7 @@ CPPFLAGS += \
 	-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))" -DBB_BT=AUTOCONF_TIMESTAMP
+	-D"BB_VER=KBUILD_STR($(BB_VER))"
 
 CFLAGS += $(call cc-option,-Wall,)
 CFLAGS += $(call cc-option,-Wshadow,)
@@ -25,6 +25,7 @@ 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
@@ -52,6 +53,12 @@ CFLAGS += $(call cc-option,-fno-builtin-strlen -finline-limit=0 -fomit-frame-poi
 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..
@@ -68,12 +75,23 @@ 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)
@@ -85,6 +103,7 @@ endif
 
 ifeq ($(CONFIG_STATIC),y)
 CFLAGS_busybox += -static
+PKG_CONFIG_FLAGS += --static
 endif
 
 ifeq ($(CONFIG_PIE),y)
@@ -97,31 +116,44 @@ CFLAGS += $(strip $(subst ",,$(CONFIG_EXTRA_CFLAGS)))
 #"))
 endif
 
-ifneq ($(CONFIG_CROSS_COMPILER_PREFIX),"arm-linux-androideabi-")
+# Note: both "" (string consisting of two quote chars) and empty string
+# are possible, and should be skipped below.
+ifneq ($(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
-# Android libc has no crypt. TODO: make a generic CONFIG_LINK_WITH_CRYPT option?
 LDLIBS += m
 endif
 
-ifneq ($(CONFIG_SYSROOT),)
-CFLAGS += --sysroot=$(CONFIG_SYSROOT)
-export SYSROOT=$(CONFIG_SYSROOT)
-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)
-# libpam uses libpthread, so for static builds busybox must be linked to
-# libpthread. On some platforms that requires an explicit -lpthread, so
-# it should be in LDLIBS. For non-static builds, scripts/trylink will
-# take care of removing -lpthread if possible. (Not bothering to check
-# CONFIG_STATIC because even in a non-static build it could be that the
-# only libpam available is libpam.a, so -lpthread could still be
-# needed.)
-LDLIBS += pam pam_misc pthread
+LDLIBS += pam pam_misc
 endif
 
 ifeq ($(CONFIG_SELINUX),y)
-LDLIBS += selinux sepol
+SELINUX_PC_MODULES = libselinux libsepol
+$(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)
@@ -143,7 +175,7 @@ SKIP_STRIP = y
 endif
 
 ifneq ($(CONFIG_EXTRA_LDFLAGS),)
-EXTRA_LDFLAGS += $(strip $(subst ",,$(CONFIG_EXTRA_LDFLAGS)))
+LDFLAGS += $(strip $(subst ",,$(CONFIG_EXTRA_LDFLAGS)))
 #"))
 endif