Q:

How to fix "IPA processing failed" error in xcode 11? 

When I tried to create IPA file using Distribute APP option.  It gave "IPA processing failed" error. 
I have checked logs file: IDEDistribution.standard.log file. 

2019-08-06 18:36:52 +0000  warning: Configuration issue: platform
  iPhoneSimulator.platform doesn't have any non-simulator SDKs; ignoring
  it Scanning IPA... 2019-08-06 18:36:52 +0000  Assertion failed:
  Expected 4 archs in otool output:
  /var/folders/4t/rpjk7pd55t16jfrd32y98gf0lb2t68/T/IDEDistributionOptionThinning.~~~a4cZJc/Payload/demo.app/Frameworks/AppAuth.framework/AppAuth:
  Mach header
        magic cputype cpusubtype  caps    filetype ncmds sizeofcmds      flags MH_MAGIC_64  X86_64        ALL  0x00       DYLIB    23
  3680   NOUNDEFS DYLDLINK TWOLEVEL NO_REEXPORTED_DYLIBS Load command 0

A:

I faced same issue. I have fix this issue used this script. 
  Please follow the same steps. 

Build Phases -> plus button -> to create New Run Script Phase
 APP_PATH="${TARGET_BUILD_DIR}/${WRAPPER_NAME}"

find "$APP_PATH" -name '*.framework' -type d | while read -r FRAMEWORK
do
FRAMEWORK_EXECUTABLE_NAME=$(defaults read "$FRAMEWORK/Info.plist" CFBundleExecutable)
FRAMEWORK_EXECUTABLE_PATH="$FRAMEWORK/$FRAMEWORK_EXECUTABLE_NAME"
echo "Executable is $FRAMEWORK_EXECUTABLE_PATH"
echo $(lipo -info "$FRAMEWORK_EXECUTABLE_PATH")

FRAMEWORK_TMP_PATH="$FRAMEWORK_EXECUTABLE_PATH-tmp"

case "${TARGET_BUILD_DIR}" in
*"iphonesimulator")
    echo "No need to remove archs"
    ;;
*)
    if $(lipo "$FRAMEWORK_EXECUTABLE_PATH" -verify_arch "i386") ; then
    lipo -output "$FRAMEWORK_TMP_PATH" -remove "i386" "$FRAMEWORK_EXECUTABLE_PATH"
    echo "i386 architecture removed"
    rm "$FRAMEWORK_EXECUTABLE_PATH"
    mv "$FRAMEWORK_TMP_PATH" "$FRAMEWORK_EXECUTABLE_PATH"
    fi
    if $(lipo "$FRAMEWORK_EXECUTABLE_PATH" -verify_arch "x86_64") ; then
    lipo -output "$FRAMEWORK_TMP_PATH" -remove "x86_64" "$FRAMEWORK_EXECUTABLE_PATH"
    echo "x86_64 architecture removed"
    rm "$FRAMEWORK_EXECUTABLE_PATH"
    mv "$FRAMEWORK_TMP_PATH" "$FRAMEWORK_EXECUTABLE_PATH"
    fi
    ;;
esac

echo "Completed for executable $FRAMEWORK_EXECUTABLE_PATH"
echo $(lipo -info "$FRAMEWORK_EXECUTABLE_PATH")

done

A:

You should check the Embed Frameworks under Xcode > build phases. 
If your framework is introduced here, you can't use i386\x86_64 in your framework.  Because the Embed Frameworks are copied to the application.  To control the size of the application, the frameworks in the Embed Frameworks are required to be the most streamlined. 
You can use Link Binary With Libraries to introduce your framework, as described here: https://github.com/Carthage/Carthage/issues/1046
Note that you need to add a new Run Script and add your framework to it, or it will crash. 

A:

1.uncheck "Rebuild from bitcode",
2.click next fast fast fast. ( speed is also important.) 

if not , it will show IPA processing failed.