uclibc-ng/Rules.mak

# Rules.make for uClibc
#
# Copyright (C) 2000-2008 Erik Andersen <andersen@uclibc.org>
#
# Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
#

# make nano-doc
# FOO = bar  -- recursively expanded variable. Value is remebered verbatim.
#               If it contains references to other variables, these references
#               are expanded whenever this variable is _substituted_.
# FOO := bar -- simply expanded variable. Right hand is expanded when
#               the variable is _defined_. Therefore faster than =.
# FOO ?= bar -- set a value only if it is not already set
#               (behaves as =, not :=).
# FOO += bar -- append; if FOO is not defined, acts like = (not :=).


# check for proper make version
ifneq ($(findstring x3.7,x$(MAKE_VERSION)),)
$(error Your make is too old $(MAKE_VERSION). Go get at least 3.80)
endif

#-----------------------------------------------------------
# This file contains rules which are shared between multiple
# Makefiles.  All normal configuration options live in the
# file named ".config".  Don't mess with this file unless
# you know what you are doing.


#-----------------------------------------------------------
# If you are running a cross compiler, you will want to set
# 'CROSS' to something more interesting ...  Target
# architecture is determined by asking the CC compiler what
# arch it compiles things for, so unless your compiler is
# broken, you should not need to specify TARGET_ARCH.
#
# Most people will set this stuff on the command line, i.e.
#        make CROSS=arm-linux-
# will build uClibc for 'arm'.

ifndef CROSS
CROSS=
endif
CC         = $(CROSS)gcc
AR         = $(CROSS)ar
LD         = $(CROSS)ld
NM         = $(CROSS)nm
STRIPTOOL  = $(CROSS)strip

INSTALL    = install
LN         = ln
RM         = rm -f
TAR        = tar
SED        = sed
AWK        = awk

STRIP_FLAGS ?= -x -R .note -R .comment

## unused? if yes, remove after 0.9.31
## UNIFDEF := $(top_builddir)extra/scripts/unifdef

# Select the compiler needed to build binaries for your development system
HOSTCC     = gcc
BUILD_CFLAGS = -Os -Wall

#---------------------------------------------------------
# Nothing beyond this point should ever be touched by mere
# mortals.  Unless you hang out with the gods, you should
# probably leave all this stuff alone.

# strip quotes
qstrip = $(strip $(subst ",,$(1)))
#"))

# Pull in the user's uClibc configuration
ifeq ($(filter $(noconfig_targets),$(MAKECMDGOALS)),)
-include $(top_builddir).config
endif
TARGET_ARCH:=$(call qstrip,$(TARGET_ARCH))
ifeq ($(TARGET_ARCH),)
ARCH ?= $(shell uname -m | $(SED) -e s/i.86/i386/ \
				  -e s/sun.*/sparc/ -e s/sparc.*/sparc/ \
				  -e s/arm.*/arm/ -e s/sa110/arm/ \
				  -e s/sh.*/sh/ \
				  -e s/s390x/s390/ -e s/parisc.*/hppa/ \
				  -e s/ppc.*/powerpc/ -e s/mips.*/mips/ \
				  -e s/xtensa.*/xtensa/ )
else
ARCH = $(TARGET_ARCH)
endif
export ARCH

# Make certain these contain a final "/", but no "//"s.
TARGET_SUBARCH:=$(call qstrip,$(shell grep -s '^TARGET_SUBARCH' $(top_builddir)/.config | $(SED) -e 's/^TARGET_SUBARCH=//'))
TARGET_SUBARCH:=$(call qstrip,$(TARGET_SUBARCH))
RUNTIME_PREFIX:=$(strip $(subst //,/, $(subst ,/, $(call qstrup,$(RUNTIME_PREFIX)))))
DEVEL_PREFIX:=$(strip $(subst //,/, $(subst ,/, $(call qstrip,$(DEVEL_PREFIX)))))
KERNEL_HEADERS:=$(strip $(subst //,/, $(subst ,/, $(call qstrip,$(KERNEL_HEADERS)))))
export RUNTIME_PREFIX DEVEL_PREFIX KERNEL_HEADERS


# Now config hard core
MAJOR_VERSION := 0
MINOR_VERSION := 9
SUBLEVEL      := 30
EXTRAVERSION  :=-git
VERSION       := $(MAJOR_VERSION).$(MINOR_VERSION).$(SUBLEVEL)
ifneq ($(EXTRAVERSION),)
VERSION       := $(VERSION)$(EXTRAVERSION)
endif
# Ensure consistent sort order, 'gcc -print-search-dirs' behavior, etc.
LC_ALL := C
export MAJOR_VERSION MINOR_VERSION SUBLEVEL VERSION LC_ALL

LIBC := libc
SHARED_MAJORNAME := $(LIBC).so.$(MAJOR_VERSION)
ifneq ($(findstring  $(TARGET_ARCH) , hppa64 ia64 mips64 powerpc64 s390x sparc64 x86_64 ),)
UCLIBC_LDSO_NAME := ld64-uClibc
ARCH_NATIVE_BIT := 64
else
UCLIBC_LDSO_NAME := ld-uClibc
ARCH_NATIVE_BIT := 32
endif
UCLIBC_LDSO := $(UCLIBC_LDSO_NAME).so.$(MAJOR_VERSION)
NONSHARED_LIBNAME := uclibc_nonshared.a
libc := $(top_builddir)lib/$(SHARED_MAJORNAME)
libc.depend := $(top_builddir)lib/$(SHARED_MAJORNAME:.$(MAJOR_VERSION)=)
interp := $(top_builddir)lib/interp.os
ldso := $(top_builddir)lib/$(UCLIBC_LDSO)
headers_dep := $(top_builddir)include/bits/sysnum.h
sub_headers := $(headers_dep)

#LIBS :=$(interp) -L$(top_builddir)lib -lc
LIBS := $(interp) -L$(top_builddir)lib $(libc:.$(MAJOR_VERSION)=)

# Make sure DESTDIR and PREFIX can be used to install
# PREFIX is a uClibcism while DESTDIR is a common GNUism
ifndef PREFIX
PREFIX = $(DESTDIR)
endif

ifneq ($(HAVE_SHARED),y)
libc :=
interp :=
ldso :=
endif

comma:=,
space:= #

ifndef CROSS
CROSS=$(call qstrip,$(CROSS_COMPILER_PREFIX))
endif

# A nifty macro to make testing gcc features easier
check_gcc=$(shell \
	if $(CC) $(1) -S -o /dev/null -xc /dev/null > /dev/null 2>&1; \
	then echo "$(1)"; else echo "$(2)"; fi)
check_as=$(shell \
	if $(CC) -Wa,$(1) -Wa,-Z -c -o /dev/null -xassembler /dev/null > /dev/null 2>&1; \
	then echo "-Wa,$(1)"; fi)
check_ld=$(shell \
	if $(LD) $(1) -o /dev/null -b binary /dev/null > /dev/null 2>&1; \
	then echo "$(1)"; fi)

ARFLAGS:=cr


# Flags in OPTIMIZATION are used only for non-debug builds

OPTIMIZATION:=
# Use '-Os' optimization if available, else use -O2, allow Config to override
OPTIMIZATION+=$(call check_gcc,-Os,-O2)
# Use the gcc 3.4 -funit-at-a-time optimization when available
OPTIMIZATION+=$(call check_gcc,-funit-at-a-time,)

GCC_MAJOR_VER?=$(shell $(CC) -dumpversion | cut -d . -f 1)
#GCC_MINOR_VER?=$(shell $(CC) -dumpversion | cut -d . -f 2)

ifeq ($(GCC_MAJOR_VER),4)
# shrinks code, results are from 4.0.2
# 0.36%
OPTIMIZATION+=$(call check_gcc,-fno-tree-loop-optimize,)
# 0.34%
OPTIMIZATION+=$(call check_gcc,-fno-tree-dominator-opts,)
# 0.1%
OPTIMIZATION+=$(call check_gcc,-fno-strength-reduce,)
endif


# CPU_CFLAGS-y contain options which are not warnings,
# not include or library paths, and not optimizations.

# Why -funsigned-char: I hunted a bug related to incorrect
# sign extension of 'char' type for 10 hours straight. Not fun.
CPU_CFLAGS-y := -funsigned-char -fno-builtin

CPU_CFLAGS-y += $(call check_gcc,-fno-asm,)

LDADD_LIBFLOAT=
ifeq ($(UCLIBC_HAS_SOFT_FLOAT),y)
# If -msoft-float isn't supported, we want an error anyway.
# Hmm... might need to revisit this for arm since it has 2 different
# soft float encodings.
ifneq ($(TARGET_ARCH),nios)
ifneq ($(TARGET_ARCH),nios2)
ifneq ($(TARGET_ARCH),sh)
CPU_CFLAGS-y += -msoft-float
endif
endif
endif
ifeq ($(TARGET_ARCH),arm)
# No longer needed with current toolchains, but leave it here for now.
# If anyone is actually still using gcc 2.95 (say), they can uncomment it.
#    LDADD_LIBFLOAT=-lfloat
endif
endif

CPU_CFLAGS-y += $(call check_gcc,-std=gnu99,)

CPU_CFLAGS-$(UCLIBC_FORMAT_SHARED_FLAT) += -mid-shared-library
CPU_CFLAGS-$(UCLIBC_FORMAT_FLAT_SEP_DATA) += -msep-data

CPU_LDFLAGS-$(ARCH_LITTLE_ENDIAN) += -Wl,-EL
CPU_LDFLAGS-$(ARCH_BIG_ENDIAN)    += -Wl,-EB

PICFLAG-y := -fPIC
PICFLAG-$(UCLIBC_FORMAT_FDPIC_ELF) := -mfdpic
PICFLAG := $(PICFLAG-y)
PIEFLAG_NAME:=-fPIE

# Some nice CPU specific optimizations
ifeq ($(TARGET_ARCH),i386)
	OPTIMIZATION+=$(call check_gcc,-fomit-frame-pointer,)

ifeq ($(CONFIG_386)$(CONFIG_486)$(CONFIG_586)$(CONFIG_586MMX),y)
	# Non-SSE capable processor.
	# NB: this may make SSE insns segfault!
	# -O1 -march=pentium3, -Os -msse etc are known to be affected.
	# See http://gcc.gnu.org/bugzilla/show_bug.cgi?id=13685
	# -m32 is needed if host is 64-bit
	OPTIMIZATION+=$(call check_gcc,-m32 -mpreferred-stack-boundary=2,)
else
	OPTIMIZATION+=$(call check_gcc,-mpreferred-stack-boundary=4,)
endif

	# Choice of alignment (please document why!)
	#  -falign-labels: in-line labels
	#  (reachable by normal code flow, aligning will insert nops
	#  which will be executed - may even make things slower)
	#  -falign-jumps: reachable only by a jump
	# Generic: no alignment at all (smallest code)
	GCC_FALIGN=$(call check_gcc,-falign-functions=1 -falign-jumps=1 -falign-labels=1 -falign-loops=1,-malign-jumps=1 -malign-loops=1)
ifeq ($(CONFIG_K7),y)
	# Align functions to four bytes, use default for jumps and loops (why?)
	GCC_FALIGN=$(call check_gcc,-falign-functions=4 -falign-labels=1,-malign-functions=4)
endif
ifeq ($(CONFIG_CRUSOE),y)
	# Use compiler's default for functions, jumps and loops (why?)
	GCC_FALIGN=$(call check_gcc,-falign-functions=0 -falign-labels=1,-malign-functions=0)
endif
ifeq ($(CONFIG_CYRIXIII),y)
	# Use compiler's default for functions, jumps and loops (why?)
	GCC_FALIGN=$(call check_gcc,-falign-functions=0 -falign-labels=1,-malign-functions=0)
endif
	OPTIMIZATION+=$(GCC_FALIGN)

	# Putting each function and data object into its own section
	# allows for kbytes of less text if users link against static uclibc
	# using ld --gc-sections.
	# ld 2.18 can't do that (yet?) for shared libraries, so we itself
	# do not use --gc-sections at shared lib link time.
	# However, in combination with sections being sorted by alignment
	# it does result in much reduced padding:
	#   text    data     bss     dec     hex
	# 235319    1472    5992  242783   3b45f old.so
	# 234104    1472    5980  241556   3af94 new.so
	# Without -ffunction-sections, all functions will get aligned
	# to 4 byte boundary by as/ld. This is arguably a bug in as.
	# It specifies 4 byte align for .text even if not told to do so:
	# Idx Name          Size      VMA       LMA       File off  Algn
	#   0 .text         xxxxxxxx  00000000  00000000  xxxxxxxx  2**2 <===!
	CPU_CFLAGS-y  += $(call check_gcc,-ffunction-sections -fdata-sections,)
ifneq ($(call check_ld,--sort-common),)
	CPU_LDFLAGS-y += -Wl,--sort-common
endif
ifneq ($(call check_ld,--sort-section alignment),)
	CPU_LDFLAGS-y += -Wl,--sort-section,alignment
endif

	CPU_LDFLAGS-y+=-m32
	CPU_CFLAGS-y+=-m32
	CPU_CFLAGS-$(CONFIG_386)+=-march=i386
	CPU_CFLAGS-$(CONFIG_486)+=-march=i486
	CPU_CFLAGS-$(CONFIG_ELAN)+=-march=i486
	CPU_CFLAGS-$(CONFIG_586)+=-march=i586
	CPU_CFLAGS-$(CONFIG_586MMX)+=$(call check_gcc,-march=pentium-mmx,-march=i586)
	CPU_CFLAGS-$(CONFIG_686)+=-march=i686
	CPU_CFLAGS-$(CONFIG_PENTIUMII)+=$(call check_gcc,-march=pentium2,-march=i686)
	CPU_CFLAGS-$(CONFIG_PENTIUMIII)+=$(call check_gcc,-march=pentium3,-march=i686)
	CPU_CFLAGS-$(CONFIG_PENTIUM4)+=$(call check_gcc,-march=pentium4,-march=i686)
	CPU_CFLAGS-$(CONFIG_K6)+=$(call check_gcc,-march=k6,-march=i586)
	CPU_CFLAGS-$(CONFIG_K7)+=$(call check_gcc,-march=athlon,-march=i686)
	CPU_CFLAGS-$(CONFIG_CRUSOE)+=-march=i686
	CPU_CFLAGS-$(CONFIG_WINCHIPC6)+=$(call check_gcc,-march=winchip-c6,-march=i586)
	CPU_CFLAGS-$(CONFIG_WINCHIP2)+=$(call check_gcc,-march=winchip2,-march=i586)
	CPU_CFLAGS-$(CONFIG_CYRIXIII)+=$(call check_gcc,-march=c3,-march=i486)
	CPU_CFLAGS-$(CONFIG_NEHEMIAH)+=$(call check_gcc,-march=c3-2,-march=i686)
endif

ifeq ($(TARGET_ARCH),sparc)
	CPU_CFLAGS-$(CONFIG_SPARC_V7)+=-mcpu=v7
	CPU_CFLAGS-$(CONFIG_SPARC_V8)+=-mcpu=v8
	CPU_CFLAGS-$(CONFIG_SPARC_V9)+=-mcpu=v9
	CPU_CFLAGS-$(CONFIG_SPARC_V9B)+=$(call check_gcc,-mcpu=v9b,-mcpu=ultrasparc)
endif

ifeq ($(TARGET_ARCH),arm)
	OPTIMIZATION+=-fstrict-aliasing
	CPU_CFLAGS-$(ARCH_LITTLE_ENDIAN)+=-mlittle-endian
	CPU_CFLAGS-$(ARCH_BIG_ENDIAN)+=-mbig-endian
	CPU_CFLAGS-$(CONFIG_GENERIC_ARM)+=
	CPU_CFLAGS-$(CONFIG_ARM610)+=-mtune=arm610 -march=armv3
	CPU_CFLAGS-$(CONFIG_ARM710)+=-mtune=arm710 -march=armv3
	CPU_CFLAGS-$(CONFIG_ARM7TDMI)+=-mtune=arm7tdmi -march=armv4t
	CPU_CFLAGS-$(CONFIG_ARM720T)+=-mtune=arm7tdmi -march=armv4t
	CPU_CFLAGS-$(CONFIG_ARM920T)+=-mtune=arm9tdmi -march=armv4t
	CPU_CFLAGS-$(CONFIG_ARM922T)+=-mtune=arm9tdmi -march=armv4t
	CPU_CFLAGS-$(CONFIG_ARM926T)+=-mtune=arm9tdmi -march=armv5t
	CPU_CFLAGS-$(CONFIG_ARM10T)+=-mtune=arm10tdmi -march=armv5t
	CPU_CFLAGS-$(CONFIG_ARM1136JF_S)+=-mtune=arm1136jf-s -march=armv6
	CPU_CFLAGS-$(CONFIG_ARM1176JZ_S)+=-mtune=arm1176jz-s -march=armv6
	CPU_CFLAGS-$(CONFIG_ARM1176JZF_S)+=-mtune=arm1176jzf-s -march=armv6
	CPU_CFLAGS-$(CONFIG_ARM_SA110)+=-mtune=strongarm110 -march=armv4
	CPU_CFLAGS-$(CONFIG_ARM_SA1100)+=-mtune=strongarm1100 -march=armv4
	CPU_CFLAGS-$(CONFIG_ARM_XSCALE)+=$(call check_gcc,-mtune=xscale,-mtune=strongarm110)
	CPU_CFLAGS-$(CONFIG_ARM_XSCALE)+=-march=armv5te -Wa,-mcpu=xscale
 	CPU_CFLAGS-$(CONFIG_ARM_IWMMXT)+=-march=iwmmxt -Wa,-mcpu=iwmmxt -mabi=iwmmxt
 	CPU_CFLAGS-$(CONFIG_ARM_CORTEX_M3)+=-mcpu=cortex-m3 -mthumb
 	CPU_CFLAGS-$(CONFIG_ARM_CORTEX_M1)+=-mcpu=cortex-m1 -mthumb
endif

ifeq ($(TARGET_ARCH),mips)
	CPU_CFLAGS-$(CONFIG_MIPS_ISA_1)+=-mips1
	CPU_CFLAGS-$(CONFIG_MIPS_ISA_2)+=-mips2 -mtune=mips2
	CPU_CFLAGS-$(CONFIG_MIPS_ISA_3)+=-mips3 -mtune=mips3
	CPU_CFLAGS-$(CONFIG_MIPS_ISA_4)+=-mips4 -mtune=mips4
	CPU_CFLAGS-$(CONFIG_MIPS_ISA_MIPS32)+=-mips32 -mtune=mips32
	CPU_CFLAGS-$(CONFIG_MIPS_ISA_MIPS32R2)+=-march=mips32r2 -mtune=mips32r2
	CPU_CFLAGS-$(CONFIG_MIPS_ISA_MIPS64)+=-mips64 -mtune=mips32
	ifeq ($(strip $(ARCH_BIG_ENDIAN)),y)
		CPU_LDFLAGS-$(CONFIG_MIPS_N64_ABI)+=-Wl,-melf64btsmip
		CPU_LDFLAGS-$(CONFIG_MIPS_O32_ABI)+=-Wl,-melf32btsmip
	endif
	ifeq ($(strip $(ARCH_LITTLE_ENDIAN)),y)
		CPU_LDFLAGS-$(CONFIG_MIPS_N64_ABI)+=-Wl,-melf64ltsmip
		CPU_LDFLAGS-$(CONFIG_MIPS_O32_ABI)+=-Wl,-melf32ltsmip
	endif
	CPU_CFLAGS-$(CONFIG_MIPS_N64_ABI)+=-mabi=64
	CPU_CFLAGS-$(CONFIG_MIPS_O32_ABI)+=-mabi=32
	CPU_CFLAGS-$(CONFIG_MIPS_N32_ABI)+=-mabi=n32
endif

ifeq ($(TARGET_ARCH),nios)
	CPU_LDFLAGS-y+=-Wl,-m32
	CPU_CFLAGS-y+=-Wl,-m32
endif

ifeq ($(TARGET_ARCH),sh)
	OPTIMIZATION+=-fstrict-aliasing
	OPTIMIZATION+= $(call check_gcc,-mprefergot,)
	CPU_CFLAGS-$(ARCH_LITTLE_ENDIAN)+=-ml
	CPU_CFLAGS-$(ARCH_BIG_ENDIAN)+=-mb
	CPU_CFLAGS-$(CONFIG_SH2)+=-m2
	CPU_CFLAGS-$(CONFIG_SH3)+=-m3
ifeq ($(UCLIBC_HAS_FPU),y)
	CPU_CFLAGS-$(CONFIG_SH2A)+=-m2a
	CPU_CFLAGS-$(CONFIG_SH4)+=-m4
else
	CPU_CFLAGS-$(CONFIG_SH2A)+=-m2a-nofpu
	CPU_CFLAGS-$(CONFIG_SH4)+=-m4-nofpu
endif
endif

ifeq ($(TARGET_ARCH),sh64)
	OPTIMIZATION+=-fstrict-aliasing
	CPU_CFLAGS-$(ARCH_LITTLE_ENDIAN):=-ml
	CPU_CFLAGS-$(ARCH_BIG_ENDIAN):=-mb
	CPU_CFLAGS-$(CONFIG_SH5)+=-m5-32media
endif

ifeq ($(TARGET_ARCH),h8300)
	SYMBOL_PREFIX=_
	CPU_LDFLAGS-$(CONFIG_H8300H)+= -Wl,-ms8300h
	CPU_LDFLAGS-$(CONFIG_H8S)   += -Wl,-ms8300s
	CPU_CFLAGS-$(CONFIG_H8300H) += -mh -mint32
	CPU_CFLAGS-$(CONFIG_H8S)    += -ms -mint32
endif

ifeq ($(TARGET_ARCH),cris)
	CPU_LDFLAGS-$(CONFIG_CRIS)+=-Wl,-mcrislinux
	CPU_LDFLAGS-$(CONFIG_CRISV32)+=-Wl,-mcrislinux
	CPU_CFLAGS-$(CONFIG_CRIS)+=-mlinux
	PICFLAG:=-fpic
	PIEFLAG_NAME:=-fpie
endif

ifeq ($(TARGET_ARCH),m68k)
	# -fPIC is only supported for 68020 and above.  It is not supported
	# for 68000, 68010, or Coldfire.
	PICFLAG:=-fpic
	PIEFLAG_NAME:=-fpie
endif

ifeq ($(TARGET_ARCH),powerpc)
# PowerPC can hold 8192 entries in its GOT with -fpic which is more than
# enough. Therefore use -fpic which will reduce code size and generates
# faster code.
	PICFLAG:=-fpic
	PIEFLAG_NAME:=-fpie
	PPC_HAS_REL16:=$(shell echo -e "\t.text\n\taddis 11,30,_GLOBAL_OFFSET_TABLE_-.@ha" | $(CC) -c -x assembler -o /dev/null -  2> /dev/null && echo -n y || echo -n n)
	CPU_CFLAGS-$(PPC_HAS_REL16)+= -DHAVE_ASM_PPC_REL16
	CPU_CFLAGS-$(CONFIG_E500) += "-D__NO_MATH_INLINES"

endif

ifeq ($(TARGET_ARCH),bfin)
	SYMBOL_PREFIX=_
ifeq ($(UCLIBC_FORMAT_FDPIC_ELF),y)
	CPU_CFLAGS-y:=-mfdpic
	CPU_LDFLAGS-y += -Wl,-melf32bfinfd
	PICFLAG:=-fpic
	PIEFLAG_NAME:=-fpie
endif
ifeq ($(UCLIBC_FORMAT_SHARED_FLAT),y)
	PICFLAG := -mleaf-id-shared-library
endif
endif

ifeq ($(TARGET_ARCH),frv)
	CPU_LDFLAGS-$(CONFIG_FRV)+=-Wl,-melf32frvfd
	# Using -pie causes the program to have an interpreter, which is
	# forbidden, so we must make do with -shared.  Unfortunately,
	# -shared by itself would get us global function descriptors
	# and calls through PLTs, dynamic resolution of symbols, etc,
	# which would break as well, but -Bsymbolic comes to the rescue.
	export LDPIEFLAG:=-shared -Wl,-Bsymbolic
	UCLIBC_LDSO=ld.so.1
endif

ifeq ($(strip $(TARGET_ARCH)),avr32)
       CPU_CFLAGS-$(CONFIG_AVR32_AP7)  += -march=ap
       CPU_CFLAGS-$(CONFIG_LINKRELAX)  += -mrelax
       CPU_LDFLAGS-$(CONFIG_LINKRELAX) += --relax
endif

ifeq ($(TARGET_ARCH),i960)
      SYMBOL_PREFIX=_
endif

ifeq ($(TARGET_ARCH),microblaze)
      SYMBOL_PREFIX=_
endif

ifeq ($(TARGET_ARCH),v850)
      SYMBOL_PREFIX=_
endif

# Keep the check_gcc from being needlessly executed
ifndef PIEFLAG
export PIEFLAG:=$(call check_gcc,$(PIEFLAG_NAME),$(PICFLAG))
endif
# We need to keep track of both the CC PIE flag (above) as
# well as the LD PIE flag (below) because we can't rely on
# gcc passing -pie if we used -fPIE. We need to directly use -pie
# instead of -Wl,-pie as gcc picks up the wrong startfile/endfile
ifndef LDPIEFLAG
export LDPIEFLAG:=$(shell $(LD) --help 2>/dev/null | grep -q -- -pie && echo "-pie")
endif

# Check for --as-needed support in linker
ifndef LD_FLAG_ASNEEDED
_LD_FLAG_ASNEEDED:=$(shell $(LD) --help 2>/dev/null | grep -- --as-needed)
ifneq ($(_LD_FLAG_ASNEEDED),)
export LD_FLAG_ASNEEDED:=--as-needed
endif
endif
ifndef LD_FLAG_NO_ASNEEDED
ifdef LD_FLAG_ASNEEDED
export LD_FLAG_NO_ASNEEDED:=--no-as-needed
endif
endif
ifndef CC_FLAG_ASNEEDED
ifdef LD_FLAG_ASNEEDED
export CC_FLAG_ASNEEDED:=-Wl,$(LD_FLAG_ASNEEDED)
endif
endif
ifndef CC_FLAG_NO_ASNEEDED
ifdef LD_FLAG_NO_ASNEEDED
export CC_FLAG_NO_ASNEEDED:=-Wl,$(LD_FLAG_NO_ASNEEDED)
endif
endif
link.asneeded = $(if $(and $(CC_FLAG_ASNEEDED),$(CC_FLAG_NO_ASNEEDED)),$(CC_FLAG_ASNEEDED) $(1) $(CC_FLAG_NO_ASNEEDED))

# Check for AS_NEEDED support in linker script (binutils>=2.16.1 has it)
ifndef ASNEEDED
export ASNEEDED:=$(shell $(LD) --help 2>/dev/null | grep -q -- --as-needed && echo "AS_NEEDED ( $(UCLIBC_LDSO) )" || echo "$(UCLIBC_LDSO)")
endif

# Add a bunch of extra pedantic annoyingly strict checks
XWARNINGS=$(call qstrip,$(WARNINGS)) -Wstrict-prototypes -fno-strict-aliasing
ifeq ($(EXTRA_WARNINGS),y)
XWARNINGS+=-Wnested-externs -Wshadow -Wmissing-noreturn -Wmissing-format-attribute -Wformat=2
XWARNINGS+=-Wmissing-prototypes -Wmissing-declarations
XWARNINGS+=-Wnonnull -Wundef
# Works only w/ gcc-3.4 and up, can't be checked for gcc-3.x w/ check_gcc()
#XWARNINGS+=-Wdeclaration-after-statement
endif
# Seems to be unused (no ARCH_CFLAGS anywhere), delete?
# if yes, remove after 0.9.31
XARCH_CFLAGS=$(call qstrip,$(ARCH_CFLAGS))
CPU_CFLAGS=$(call qstrip,$(CPU_CFLAGS-y))

SSP_DISABLE_FLAGS ?= $(call check_gcc,-fno-stack-protector,)
ifeq ($(UCLIBC_BUILD_SSP),y)
SSP_CFLAGS := $(call check_gcc,-fno-stack-protector-all,)
SSP_CFLAGS += $(call check_gcc,-fstack-protector,)
SSP_ALL_CFLAGS ?= $(call check_gcc,-fstack-protector-all,)
else
SSP_CFLAGS := $(SSP_DISABLE_FLAGS)
endif

NOSTDLIB_CFLAGS:=$(call check_gcc,-nostdlib,)

# Collect all CFLAGS components
CFLAGS := -include $(top_srcdir)include/libc-symbols.h \
	$(XWARNINGS) $(CPU_CFLAGS) $(SSP_CFLAGS) \
	-nostdinc -I$(top_builddir)include -I$(top_srcdir)include -I. \
	-I$(top_srcdir)libc/sysdeps/linux/$(TARGET_ARCH)
ifneq ($(strip $(UCLIBC_EXTRA_CFLAGS)),"")
CFLAGS += $(call qstrip,$(UCLIBC_EXTRA_CFLAGS))
endif

# We need this to be checked within libc-symbols.h
ifneq ($(HAVE_SHARED),y)
CFLAGS += -DSTATIC
endif

LDFLAG_WARN_ONCE:=$(if $(call check_ld,--warn-once),-Wl$(comma)--warn-once)
LDFLAG_SORT_COMMON:=$(if $(call check_ld,--sort-common),-Wl$(comma)--sort-common)
LDFLAG_DISCARD_ALL:=$(if $(call check_ld,--discard-all),-Wl$(comma)--discard-all)
LDFLAGS_NOSTRIP:=$(CPU_LDFLAGS-y) -shared \
	-Wl,--warn-common $(LDFLAG_WARN_ONCE) -Wl,-z,combreloc
# binutils-2.16.1 warns about ignored sections, 2.16.91.0.3 and newer are ok
#LDFLAGS_NOSTRIP+=$(call check_ld,--gc-sections)

ifeq ($(UCLIBC_BUILD_RELRO),y)
LDFLAGS_NOSTRIP+=-Wl,-z,relro
endif

ifeq ($(UCLIBC_BUILD_NOW),y)
LDFLAGS_NOSTRIP+=-Wl,-z,now
endif

ifeq ($(LDSO_GNU_HASH_SUPPORT),y)
# Be sure that binutils support it
LDFLAGS_GNUHASH:=$(call check_ld,--hash-style=gnu)
ifeq ($(LDFLAGS_GNUHASH),)
ifneq ($(filter-out install_headers headers-y,$(MAKECMDGOALS)),)
$(error Your binutils do not support --hash-style option, while you want to use it)
endif
else
LDFLAGS_NOSTRIP += -Wl,$(LDFLAGS_GNUHASH)
endif
endif

LDFLAGS:=$(LDFLAGS_NOSTRIP) -Wl,-z,defs
ifeq ($(DODEBUG),y)
CFLAGS += -O0 -g3
else
CFLAGS += $(OPTIMIZATION) $(XARCH_CFLAGS)
endif
ifeq ($(DOSTRIP),y)
LDFLAGS += -Wl,-s
else
STRIPTOOL := true -Stripping_disabled
endif

ifeq ($(DOMULTI),y)
# we try to compile all sources at once into an object (IMA), but
# gcc-3.3.x does not support it
# gcc-3.4.x supports it, but does not need and support --combine. though fails on many sources
# gcc-4.0.x supports it, supports the --combine flag, but does not need it
# gcc-4.1(200506xx) supports it, but needs the --combine flag, else libs are useless
ifeq ($(GCC_MAJOR_VER),3)
DOMULTI:=n
else
CFLAGS+=$(call check_gcc,--combine,)
endif
else
DOMULTI:=n
endif

ifneq ($(strip $(UCLIBC_EXTRA_LDFLAGS)),"")
LDFLAGS += $(call qstrip,$(UCLIBC_EXTRA_LDFLAGS))
endif

ifeq ($(UCLIBC_HAS_THREADS),y)
ifeq ($(UCLIBC_HAS_THREADS_NATIVE),y)
	PTNAME := nptl
else
ifeq ($(LINUXTHREADS_OLD),y)
	PTNAME := linuxthreads.old
else
	PTNAME := linuxthreads
endif
endif
PTDIR := libpthread/$(PTNAME)
# set up system dependencies include dirs (NOTE: order matters!)
ifeq ($(UCLIBC_HAS_THREADS_NATIVE),y)
PTINC:=	-I$(top_srcdir)$(PTDIR)						\
	-I$(top_srcdir)$(PTDIR)/sysdeps/unix/sysv/linux/$(TARGET_ARCH)	\
	-I$(top_srcdir)$(PTDIR)/sysdeps/$(TARGET_ARCH)			\
	-I$(top_srcdir)$(PTDIR)/sysdeps/unix/sysv/linux			\
	-I$(top_srcdir)$(PTDIR)/sysdeps/pthread				\
	-I$(top_srcdir)$(PTDIR)/sysdeps/pthread/bits				\
	-I$(top_srcdir)$(PTDIR)/sysdeps/generic				\
	-I$(top_srcdir)ldso/ldso/$(TARGET_ARCH)			\
	-I$(top_srcdir)ldso/include
#
# Test for TLS if NPTL support was selected.
#
GCC_HAS_TLS=$(shell \
	echo "extern __thread int foo;" | $(CC) -o /dev/null -S -xc - 2>&1)
ifneq ($(GCC_HAS_TLS),)
gcc_tls_test_fail:
	@echo "####";
	@echo "#### Your compiler does not support TLS and you are trying to build uClibc";
	@echo "#### with NPTL support. Upgrade your binutils and gcc to versions which";
	@echo "#### support TLS for your architecture. Do not contact uClibc maintainers";
	@echo "#### about this problem.";
	@echo "####";
	@echo "#### Exiting...";
	@echo "####";
	@exit 1;
endif
else
PTINC := \
	-I$(top_srcdir)$(PTDIR)/sysdeps/unix/sysv/linux/$(TARGET_ARCH) \
	-I$(top_srcdir)$(PTDIR)/sysdeps/$(TARGET_ARCH) \
	-I$(top_srcdir)$(PTDIR)/sysdeps/unix/sysv/linux \
	-I$(top_srcdir)$(PTDIR)/sysdeps/pthread \
	-I$(top_srcdir)$(PTDIR) \
	-I$(top_srcdir)libpthread
endif
CFLAGS+=$(PTINC)
else
	PTNAME :=
	PTINC  :=
endif
CFLAGS += -I$(KERNEL_HEADERS)

#CFLAGS += -iwithprefix include-fixed -iwithprefix include
CC_IPREFIX := $(shell $(CC) --print-file-name=include)
CC_INC := -isystem $(dir $(CC_IPREFIX))include-fixed -isystem $(CC_IPREFIX)
CFLAGS += $(CC_INC)

ifneq ($(DOASSERTS),y)
CFLAGS+=-DNDEBUG
endif

ifeq ($(SYMBOL_PREFIX),_)
CFLAGS+=-D__UCLIBC_UNDERSCORES__
endif

# Keep the check_as from being needlessly executed
ifndef ASFLAGS_NOEXEC
ifeq ($(UCLIBC_BUILD_NOEXECSTACK),y)
export ASFLAGS_NOEXEC := $(call check_as,--noexecstack)
else
export ASFLAGS_NOEXEC :=
endif
endif
ASFLAGS = $(ASFLAGS_NOEXEC)

LIBGCC_CFLAGS ?= $(CFLAGS) $(CPU_CFLAGS-y)
LIBGCC:=$(shell $(CC) $(LIBGCC_CFLAGS) -print-libgcc-file-name)
LIBGCC_DIR:=$(dir $(LIBGCC))

# moved from libpthread/linuxthreads
ifeq ($(UCLIBC_CTOR_DTOR),y)
SHARED_START_FILES:=$(top_builddir)lib/crti.o $(LIBGCC_DIR)crtbeginS.o
SHARED_END_FILES:=$(LIBGCC_DIR)crtendS.o $(top_builddir)lib/crtn.o
endif

LOCAL_INSTALL_PATH := install_dir