Added the Xcode 12 carthage workaround script for Travis

.travis.yml

@@ -33,8 +33,8 @@ script:
   - pod install --project-directory=Example
   - xcodebuild build -workspace Example/SDWebImageSwiftUI.xcworkspace -scheme SDWebImageSwiftUIDemo -destination 'name=iPhone 11 Pro Max' -configuration Debug | xcpretty -c
 
-  - carthage update --configuration Debug
-  - xcodebuild build -project SDWebImageSwiftUI.xcodeproj -scheme 'SDWebImageSwiftUI' -sdk iphonesimulator -configuration Debug | xcpretty -c
+  - ./carthage.sh update --configuration Debug
+  - xcodebuild build -project SDWebImageSwiftUI.xcodeproj -scheme 'SDWebImageSwiftUI' -destination 'name=iPhone 11 Pro Max' -configuration Debug | xcpretty -c
 
   - echo Clean DerivedData
   - rm -rf ~/Library/Developer/Xcode/DerivedData/

carthage.sh

@@ -0,0 +1,19 @@
+# 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 "$@"