busybox: tweak help text

[oweals/busybox.git] / Makefile.flags

diff --git a/Makefile.flags b/Makefile.flags
index e31480204e885f58ca41e6299d53df6a911c47b3..f745c2fdfed0ff4ece40fbd0a415d242cdad2437 100644 (file)
--- a/Makefile.flags
+++ b/Makefile.flags
@@ -4,7 +4,7 @@
 
 BB_VER = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION)
 export BB_VER
-SKIP_STRIP = n
+SKIP_STRIP ?= n
 
 # -std=gnu99 needed for [U]LLONG_MAX on some systems
 CPPFLAGS += $(call cc-option,-std=gnu99,)
@@ -23,6 +23,7 @@ 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,)
 # warn about C99 declaration after statement
 CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
@@ -31,6 +32,16 @@ CFLAGS += $(call cc-option,-Wdeclaration-after-statement,)
 
 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)
@@ -47,14 +58,14 @@ CFLAGS += $(call cc-option,-falign-functions=1 -falign-jumps=1 -falign-labels=1
 #CFLAGS += $(call cc-option,-Wconversion,)
 
 ifneq ($(CONFIG_DEBUG),y)
-CFLAGS += $(call cc-option,-Os,)
+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,)
+CFLAGS += $(call cc-option,-Os,$(call cc-option,-O2,))
 endif
 endif
 
@@ -81,10 +92,35 @@ 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
+CRYPT_AVAILABLE := $(shell echo 'int main(void){return 0;}' | $(CC) $(CFLAGS) -lcrypt -o /dev/null -xc - >/dev/null 2>&1 && echo "y")
+ifeq ($(CRYPT_AVAILABLE),y)
 LDLIBS += m crypt
+else
+LDLIBS += m
+endif
 
 ifeq ($(CONFIG_PAM),y)
-LDLIBS += pam pam_misc
+# 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
 endif
 
 ifeq ($(CONFIG_SELINUX),y)
@@ -99,16 +135,26 @@ ifeq ($(CONFIG_DMALLOC),y)
 LDLIBS += dmalloc
 endif
 
-# If a flat binary should be built, CFLAGS_busybox="-Wl,-elf2flt"
+# 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 "-Wl,-elf2flt" into).
-W_ELF2FLT = -Wl,-elf2flt
+# 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),)
+EXTRA_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!)