iOS 打包32bit&64 universal-framework

1. 在原来的基础上添加新的framework target (32bit)
2. duplicate 64bit framework, 然后做相应改动，依赖于32bit target
3. build above target
4. otools -L xxx64.framework/xxx64 查看installname, use install_name_tool -id @rpath/xxx.framework/xxx xxx64.framework/xxx64
   修改install name
5. create aggregate target, add run script to combine 32&64 target(use lip tools)
   lipo -create xxx32.framework/xxx32 xxx64.framework/xxx64 xxx,
   cp xxx.framework newpath/xxx.framework
   replace newpath/xxx.framework/xxx with combined target
   ps: 这步也可以使用手工lipo生成
6. 在demo project中使用：general->embeded binaries
   add import <xxx.framework/xxx.h>

Xcode Script to Lipo Tool

# Sets the target folders and the final framework product.
FMK_NAME="FI"  
FMK_VERSION="A"

# Install dir will be the final output to the framework.
# The following line create it in the root folder of the current project.
INSTALL_DIR=${SRCROOT}/Products/${FMK_NAME}.framework

# Working dir will be deleted after the framework creation.
WRK_DIR=build  
DEVICE_DIR=${WRK_DIR}/Release-iphoneos/${FMK_NAME}.framework  
SIMULATOR_DIR=${WRK_DIR}/Release-iphonesimulator/${FMK_NAME}.framework

# Building both architectures.
xcodebuild -configuration "Release" -target "${FMK_NAME}" -sdk iphoneos  
xcodebuild -configuration "Release" -target "${FMK_NAME}" -sdk iphonesimulator

# Cleaning the oldest.
if [ -d "${INSTALL_DIR}" ]  
then  
rm -rf "${INSTALL_DIR}"  
fi

# Creates and renews the final product folder.
mkdir -p "${INSTALL_DIR}"  
mkdir -p "${INSTALL_DIR}/Versions"  
mkdir -p "${INSTALL_DIR}/Versions/${FMK_VERSION}"  
mkdir -p "${INSTALL_DIR}/Versions/${FMK_VERSION}/Resources"  
mkdir -p "${INSTALL_DIR}/Versions/${FMK_VERSION}/Headers"

# Creates the internal links.
# It MUST uses relative path, otherwise will not work when the folder is copied/moved.
ln -s "${FMK_VERSION}" "${INSTALL_DIR}/Versions/Current"  
ln -s "Versions/Current/Headers" "${INSTALL_DIR}/Headers"  
ln -s "Versions/Current/Resources" "${INSTALL_DIR}/Resources"  
ln -s "Versions/Current/${FMK_NAME}" "${INSTALL_DIR}/${FMK_NAME}"

# Copies the headers and resources files to the final product folder.
cp -R "${DEVICE_DIR}/Headers/" "${INSTALL_DIR}/Versions/${FMK_VERSION}/Headers/"  
cp -R "${DEVICE_DIR}/" "${INSTALL_DIR}/Versions/${FMK_VERSION}/Resources/"

# Removes the binary and header from the resources folder.
rm -r "${INSTALL_DIR}/Versions/${FMK_VERSION}/Resources/Headers" "${INSTALL_DIR}/Versions/${FMK_VERSION}/Resources/${FMK_NAME}"

# Uses the Lipo Tool to merge both binary files (i386 + armv6/armv7) into one Universal final product.
lipo -create "${DEVICE_DIR}/${FMK_NAME}" "${SIMULATOR_DIR}/${FMK_NAME}" -output "${INSTALL_DIR}/Versions/${FMK_VERSION}/${FMK_NAME}"

rm -r "${WRK_DIR}"

ps:
The important thing to realize is that the install path is built into the dylib, as part of its build process.
trouble shooting:
deep clean & relaunch Xcode !

一篇很有用的参考博客
https://medium.com/@syshen/create-an-ios-universal-framework-148eb130a46c