问题
升级Xcode12后，Carthage 配置出现问题，无法使用，出现了失败：
Carthage Update Task failed with exit code 1
原因
Well, shortly, Carthage builds fat frameworks, which means that the framework contains binaries for all supported architectures. Until Apple Sillicon was introduced it all worked just fine, but now there is a conflict as there are duplicate architectures (arm64 for devices and arm64 for simulator). This means that Carthage cannot link architecture specific frameworks to a single fat framework.
解决方案
创建脚本脚本carthage.sh，放到/usr/local/bin/目录下，然后执行如下命令
chmod +x /usr/local/bin/carthage.sh
脚本内容如下：
#carthage.sh
#Usage example: ./carthage.sh build --platform iOS
set -euo pipefail
xcconfig=$(mktemp /tmp/static.xcconfig.XXXXXX)
trap 'rm -f "$xcconfig"' INT TERM HUP EXIT
#For Xcode 12 make sure EXCLUDED_ARCHS is set to arm architectures otherwise
#the build will fail on lipo due to duplicate architectures.
CURRENT_XCODE_VERSION = $(xcodebuild -version | grep "Build version" | cut -d ' ' -f3)
echo "EXCLUDED_ARCHS__EFFECTIVE_PLATFORM_SUFFIX_simulator__NATIVE_ARCH_64_BIT_x86_64__XCODE_1200__BUILD_$CURRENT_XCODE_VERSION= arm64 arm64e armv7 armv7s armv6 armv8" >> $xcconfig
echo 'EXCLUDED_ARCHS__EFFECTIVE_PLATFORM_SUFFIX_simulator__NATIVE_ARCH_64_BIT_x86_64__XCODE_1200 = $(EXCLUDED_ARCHS__EFFECTIVE_PLATFORM_SUFFIX_simulator__NATIVE_ARCH_64_BIT_x86_64__XCODE_1200__BUILD_$(XCODE_PRODUCT_BUILD_VERSION))' >> $xcconfig
echo 'EXCLUDED_ARCHS = $(inherited) $(EXCLUDED_ARCHS__EFFECTIVE_PLATFORM_SUFFIX_$(EFFECTIVE_PLATFORM_SUFFIX)__NATIVE_ARCH_64_BIT_$(NATIVE_ARCH_64_BIT)__XCODE_$(XCODE_VERSION_MAJOR))' >> $xcconfig
export XCODE_XCCONFIG_FILE = "$xcconfig"
carthage "$@"
使用方法
carthage.sh update --platform iOS
