How do I link third party libraries like fftw3 and sndfile to an iPhone project in Xcode?

Question

I\'m trying to link third party libraries like fftw3 and sndfile to my iPhone project in Xcode3.2. I got it working in a regular Mac project by setting the \"Header Search P

Answer 1

I modified Nickun's script for Mac OS X 10.9.2, iOS 7.1, fftw-3.3.4. It also adds an arm64 slice to the fat file. Here is the script ->

#!/bin/sh

# build_lipo.sh
# build an arm64 / armv7s / armv7 / i386 / x86_64 lib of fftw3
# make sure to check that all the paths used in this script exist on your system
#
# adopted from:
# http://robertcarlsen.net/2009/07/15/cross-compiling-for-iphone-dev-884
# changed by Adam
# original: by Nickun
# http://stackoverflow.com/questions/3588904/how-to-link-third-party-libraries-like-fftw3-and-sndfile-to-an-iphone-project-in

# this is the folder where the results of our efforts will end up:
export RESULT_DIR=ios-library

# Select toolchains folder
export XCODE_TOOLCHAINS=/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain
# Select the desired iPhone SDK
export DEVROOT_IOS=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer
export SDKROOT_IOS=$DEVROOT_IOS/SDKs/iPhoneOS7.1.sdk
# Select the OSX SDK
export DEVROOT_OSX=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer
export SDKROOT_OSX=$DEVROOT_OSX/SDKs/MacOSX10.9.2.sdk

# ------------------------ i386 ---------------------------
# Do it for i386
make clean

# Restore default environment variables
unset CPPFLAGS CFLAGS CPP LD CXX LDFLAGS CXXFLAGS

export CFLAGS="-arch i386"

# TODO: error checking
./configure --enable-float --host=i386-apple-darwin9.2.0 --target=i386-apple-darwin9.2.0
make -j2

# Copy the FAT native library to a temporary location
mkdir $RESULT_DIR
cp .libs/libfftw3f.a $RESULT_DIR/libfftw3f_i386.a

# ------------------------ x86_64 ---------------------------
# Do it all again for x86_64
make clean

# Restore default environment variables
unset CPPFLAGS CFLAGS CPP LD CXX LDFLAGS CXXFLAGS

# TODO: error checking
./configure --enable-float
make -j2

# Copy the FAT native library to the temporary location
cp .libs/libfftw3f.a $RESULT_DIR/libfftw3f_x86_64.a

# ------------------------ armv7---------------------------
# Do it all again for armv7
make clean

# Restore default environment variables
unset CPPFLAGS CFLAGS CPP LD CXX LDFLAGS CXXFLAGS

# Set up relevant environment variables
export CPPFLAGS="-I$SDKROOT_IOS/usr/include/ -mfpu=neon"
export CFLAGS="$CPPFLAGS -arch armv7 -mfpu=neon -no-cpp-precomp -miphoneos-version-min=5.0 -isysroot $SDKROOT_IOS"
export LD=$XCODE_TOOLCHAINS/usr/bin/ld
export CXX="$XCODE_TOOLCHAINS/usr/bin/clang -x c++ -arch armv7 -std=gnu++11 -stdlib=libc++ -mfpu=neon"
export CC="$XCODE_TOOLCHAINS/usr/bin/clang -x c -arch armv7 -std=gnu99 -mfpu=neon"
export CXXFLAGS="$CFLAGS"

# TODO: add custom flags as necessary for package
#  remove '--enable-float' for double precision
#  and take a 'libfftw3.a' file instead
./configure --host=arm-apple-darwin --target=arm-apple-darwin --enable-float --enable-neon

make -j2

cp .libs/libfftw3f.a $RESULT_DIR/libfftw3f_armv7.a

# Copy the header file too, just for convenience
cp api/fftw3.h $RESULT_DIR/fftw3.h

# ------------------------ armv7s---------------------------
# Do it all again for i386
make clean

# Restore default environment variables
unset CPPFLAGS CFLAGS CPP LD CXX LDFLAGS CXXFLAGS

# Set up relevant environment variables
export CPPFLAGS="-I$SDKROOT_IOS/usr/include/ -mfpu=neon"
export CFLAGS="$CPPFLAGS -arch armv7s -mfpu=neon -no-cpp-precomp -miphoneos-version-min=5.0 -isysroot $SDKROOT_IOS"
export LD=$XCODE_TOOLCHAINS/usr/bin/ld
export CXX="$XCODE_TOOLCHAINS/usr/bin/clang -x c++ -arch armv7s -std=gnu++11 -stdlib=libc++ -mfpu=neon"
export CC="$XCODE_TOOLCHAINS/usr/bin/clang -x c -arch armv7s -std=gnu99 -mfpu=neon"
export CXXFLAGS="$CFLAGS"

# TODO: add custom flags as necessary for package
#  remove '--enable-float' for double precision
#  and take a 'libfftw3.a' file instead
./configure --host=arm-apple-darwin --target=arm-apple-darwin --enable-float --enable-neon

make -j2

# Copy the ARM library to a temporary location
cp .libs/libfftw3f.a $RESULT_DIR/libfftw3f_armv7s.a

# ------------------------ arm64 ---------------------------
# Do it all again for arm64
make clean

# Restore default environment variables
unset CPPFLAGS CFLAGS CPP LD CXX LDFLAGS CXXFLAGS

# Set up relevant environment variables
export CPPFLAGS="-I$SDKROOT_IOS/usr/include/ -mfpu=neon"
export CFLAGS="$CPPFLAGS -arch arm64 -mfpu=neon -no-cpp-precomp -miphoneos-version-min=5.0 -isysroot $SDKROOT_IOS"
export LD=$XCODE_TOOLCHAINS/usr/bin/ld
export CXX="$XCODE_TOOLCHAINS/usr/bin/clang -x c++ -arch arm64 -std=gnu++11 -stdlib=libc++ -mfpu=neon"
export CC="$XCODE_TOOLCHAINS/usr/bin/clang -x c -arch arm64 -std=gnu99 -mfpu=neon"
export CXXFLAGS="$CFLAGS"

# TODO: add custom flags as necessary for package
#  remove '--enable-float' for double precision
#  and take a 'libfftw3.a' file instead
./configure --host=arm-apple-darwin --target=arm-apple-darwin --enable-float --enable-neon

make -j2

# Copy the ARM library to a temporary location
cp .libs/libfftw3f.a ios-library/libfftw3f_arm64.a


# Create fat lib by combining the two versions
lipo -arch armv7 $RESULT_DIR/libfftw3f_armv7.a -arch armv7s $RESULT_DIR/libfftw3f_armv7s.a -arch i386 $RESULT_DIR/libfftw3f_i386.a -arch x86_64 $RESULT_DIR/libfftw3f_x86_64.a -arch arm64 $RESULT_DIR/libfftw3f_arm64.a -create -output $RESULT_DIR/libfftw3f.a

# Remove intermediate binaries
#rm $RESULT_DIR/libfftw3_armv7.a
#rm $RESULT_DIR/libfftw3_i386.a
#rm $RESULT_DIR/libfftw3_x86_64.a

# Unset used environment variables
unset CPPFLAGS CFLAGS CPP LD LDFLAGS CXX CXXFLAGS