blob: 640eeeca5d1f88ad3e16351bcadd13f0fcbc9499
1 | # ========================================================================== |
2 | # Build system |
3 | # ========================================================================== |
4 | |
5 | BB_VER = $(VERSION).$(PATCHLEVEL).$(SUBLEVEL)$(EXTRAVERSION) |
6 | export BB_VER |
7 | SKIP_STRIP ?= n |
8 | |
9 | # -std=gnu99 needed for [U]LLONG_MAX on some systems |
10 | CPPFLAGS += $(call cc-option,-std=gnu99,) |
11 | |
12 | CPPFLAGS += \ |
13 | -Iinclude -Ilibbb \ |
14 | $(if $(KBUILD_SRC),-Iinclude2 -I$(srctree)/include -I$(srctree)/libbb) \ |
15 | -include include/autoconf.h \ |
16 | -D_GNU_SOURCE -DNDEBUG \ |
17 | $(if $(CONFIG_LFS),-D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64) \ |
18 | -D"BB_VER=KBUILD_STR($(BB_VER))" -DBB_BT=AUTOCONF_TIMESTAMP |
19 | |
20 | CFLAGS += $(call cc-option,-Wall,) |
21 | CFLAGS += $(call cc-option,-Wshadow,) |
22 | CFLAGS += $(call cc-option,-Wwrite-strings,) |
23 | CFLAGS += $(call cc-option,-Wundef,) |
24 | CFLAGS += $(call cc-option,-Wstrict-prototypes,) |
25 | CFLAGS += $(call cc-option,-Wunused -Wunused-parameter,) |
26 | CFLAGS += $(call cc-option,-Wunused-function -Wunused-value,) |
27 | CFLAGS += $(call cc-option,-Wmissing-prototypes -Wmissing-declarations,) |
28 | CFLAGS += $(call cc-option,-Wno-format-security,) |
29 | # warn about C99 declaration after statement |
30 | CFLAGS += $(call cc-option,-Wdeclaration-after-statement,) |
31 | # If you want to add more -Wsomething above, make sure that it is |
32 | # still possible to build bbox without warnings. |
33 | |
34 | ifeq ($(CONFIG_WERROR),y) |
35 | CFLAGS += $(call cc-option,-Werror,) |
36 | ## TODO: |
37 | ## gcc version 4.4.0 20090506 (Red Hat 4.4.0-4) (GCC) is a PITA: |
38 | ## const char *ptr; ... off_t v = *(off_t*)ptr; -> BOOM |
39 | ## and no easy way to convince it to shut the hell up. |
40 | ## We have a lot of such things all over the place. |
41 | ## Classic *(off_t*)(void*)ptr does not work, |
42 | ## and I am unwilling to do crazy gcc specific ({ void *ppp = ...; }) |
43 | ## stuff in macros. This would obfuscate the code too much. |
44 | ## Maybe try __attribute__((__may_alias__))? |
45 | #CFLAGS += $(call cc-ifversion, -eq, 0404, -fno-strict-aliasing) |
46 | endif |
47 | # gcc 3.x emits bogus "old style proto" warning on find.c:alloc_action() |
48 | CFLAGS += $(call cc-ifversion, -ge, 0400, -Wold-style-definition) |
49 | |
50 | CFLAGS += $(call cc-option,-fno-builtin-strlen -finline-limit=0 -fomit-frame-pointer -ffunction-sections -fdata-sections,) |
51 | # -fno-guess-branch-probability: prohibit pseudo-random guessing |
52 | # of branch probabilities (hopefully makes bloatcheck more stable): |
53 | CFLAGS += $(call cc-option,-fno-guess-branch-probability,) |
54 | CFLAGS += $(call cc-option,-funsigned-char -static-libgcc,) |
55 | CFLAGS += $(call cc-option,-falign-functions=1 -falign-jumps=1 -falign-labels=1 -falign-loops=1,) |
56 | # Defeat .eh_frame bloat (gcc 4.6.3 x86-32 defconfig: 20% smaller busybox binary): |
57 | CFLAGS += $(call cc-option,-fno-unwind-tables,) |
58 | CFLAGS += $(call cc-option,-fno-asynchronous-unwind-tables,) |
59 | |
60 | # FIXME: These warnings are at least partially to be concerned about and should |
61 | # be fixed.. |
62 | #CFLAGS += $(call cc-option,-Wconversion,) |
63 | |
64 | ifneq ($(CONFIG_DEBUG),y) |
65 | CFLAGS += $(call cc-option,-Os,$(call cc-option,-O2,)) |
66 | else |
67 | CFLAGS += $(call cc-option,-g,) |
68 | #CFLAGS += "-D_FORTIFY_SOURCE=2" |
69 | ifeq ($(CONFIG_DEBUG_PESSIMIZE),y) |
70 | CFLAGS += $(call cc-option,-O0,) |
71 | else |
72 | CFLAGS += $(call cc-option,-Os,$(call cc-option,-O2,)) |
73 | endif |
74 | endif |
75 | |
76 | # If arch/$(ARCH)/Makefile did not override it (with, say, -fPIC)... |
77 | ARCH_FPIC ?= -fpic |
78 | ARCH_FPIE ?= -fpie |
79 | ARCH_PIE ?= -pie |
80 | |
81 | # Usage: $(eval $(call pkg_check_modules,VARIABLE-PREFIX,MODULES)) |
82 | define pkg_check_modules |
83 | $(1)_CFLAGS := $(shell $(PKG_CONFIG) $(PKG_CONFIG_FLAGS) --cflags $(2)) |
84 | $(1)_LIBS := $(shell $(PKG_CONFIG) $(PKG_CONFIG_FLAGS) --libs $(2)) |
85 | endef |
86 | |
87 | ifeq ($(CONFIG_BUILD_LIBBUSYBOX),y) |
88 | # on i386: 14% smaller libbusybox.so |
89 | # (code itself is 9% bigger, we save on relocs/PLT/GOT) |
90 | CFLAGS += $(ARCH_FPIC) |
91 | # and another 4% reduction of libbusybox.so: |
92 | # (external entry points must be marked EXTERNALLY_VISIBLE) |
93 | CFLAGS += $(call cc-option,-fvisibility=hidden) |
94 | endif |
95 | |
96 | ifeq ($(CONFIG_STATIC),y) |
97 | CFLAGS_busybox += -static |
98 | PKG_CONFIG_FLAGS += --static |
99 | endif |
100 | |
101 | ifeq ($(CONFIG_PIE),y) |
102 | CFLAGS_busybox += $(ARCH_PIE) |
103 | CFLAGS += $(ARCH_FPIE) |
104 | endif |
105 | |
106 | ifneq ($(CONFIG_EXTRA_CFLAGS),) |
107 | CFLAGS += $(strip $(subst ",,$(CONFIG_EXTRA_CFLAGS))) |
108 | #")) |
109 | endif |
110 | |
111 | # Note: both "" (string consisting of two quote chars) and empty string |
112 | # are possible, and should be skipped below. |
113 | ifneq ($(subst "",,$(CONFIG_SYSROOT)),) |
114 | CFLAGS += --sysroot=$(CONFIG_SYSROOT) |
115 | export SYSROOT=$(CONFIG_SYSROOT) |
116 | endif |
117 | |
118 | # Android has no separate crypt library |
119 | # gcc-4.2.1 fails if we try to feed C source on stdin: |
120 | # echo 'int main(void){return 0;}' | $(CC) $(CFLAGS) -lcrypt -o /dev/null -xc - |
121 | # fall back to using a temp file: |
122 | CRYPT_AVAILABLE := $(shell echo 'int main(void){return 0;}' >crypttest.c; $(CC) $(CFLAGS) -lcrypt -o /dev/null crypttest.c >/dev/null 2>&1 && echo "y"; rm crypttest.c) |
123 | ifeq ($(CRYPT_AVAILABLE),y) |
124 | LDLIBS += m crypt |
125 | else |
126 | LDLIBS += m |
127 | endif |
128 | |
129 | ifeq ($(CONFIG_PAM),y) |
130 | # libpam uses libpthread, so for static builds busybox must be linked to |
131 | # libpthread. On some platforms that requires an explicit -lpthread, so |
132 | # it should be in LDLIBS. For non-static builds, scripts/trylink will |
133 | # take care of removing -lpthread if possible. (Not bothering to check |
134 | # CONFIG_STATIC because even in a non-static build it could be that the |
135 | # only libpam available is libpam.a, so -lpthread could still be |
136 | # needed.) |
137 | LDLIBS += pam pam_misc pthread |
138 | endif |
139 | |
140 | ifeq ($(CONFIG_SELINUX),y) |
141 | ifeq ($(ANDROID_PRODUCT_OUT),) # Ignore pkgconfig on Android Builds |
142 | SELINUX_PC_MODULES = libselinux libsepol |
143 | $(eval $(call pkg_check_modules,SELINUX,$(SELINUX_PC_MODULES))) |
144 | CPPFLAGS += $(SELINUX_CFLAGS) |
145 | LDLIBS += $(if $(SELINUX_LIBS),$(SELINUX_LIBS:-l%=%),$(SELINUX_PC_MODULES:lib%=%)) |
146 | endif |
147 | endif |
148 | |
149 | ifeq ($(CONFIG_EFENCE),y) |
150 | LDLIBS += efence |
151 | endif |
152 | |
153 | ifeq ($(CONFIG_DMALLOC),y) |
154 | LDLIBS += dmalloc |
155 | endif |
156 | |
157 | # If a flat binary should be built, CFLAGS_busybox="-elf2flt" |
158 | # env var should be set for make invocation. |
159 | # Here we check whether CFLAGS_busybox indeed contains that flag. |
160 | # (For historical reasons, we also check LDFLAGS, which doesn't |
161 | # seem to be entirely correct variable to put "-elf2flt" into). |
162 | W_ELF2FLT = -elf2flt |
163 | ifneq (,$(findstring $(W_ELF2FLT),$(LDFLAGS) $(CFLAGS_busybox))) |
164 | SKIP_STRIP = y |
165 | endif |
166 | |
167 | ifneq ($(CONFIG_EXTRA_LDFLAGS),) |
168 | EXTRA_LDFLAGS += $(strip $(subst ",,$(CONFIG_EXTRA_LDFLAGS))) |
169 | #")) |
170 | endif |
171 | |
172 | ifneq ($(CONFIG_EXTRA_LDLIBS),) |
173 | LDLIBS += $(strip $(subst ",,$(CONFIG_EXTRA_LDLIBS))) |
174 | #")) |
175 | endif |
176 | |
177 | # Busybox is a stack-fatty so make sure we increase default size |
178 | # TODO: use "make stksizes" to find & fix big stack users |
179 | # (we stole scripts/checkstack.pl from the kernel... thanks guys!) |
180 | # Reduced from 20k to 16k in 1.9.0. |
181 | FLTFLAGS += -s 16000 |
182 |