title: Command CompileSwiftSources failed with a nonzero exit code Xcode 10
body: <p>I read some same issue but their solutions did not work for me. My project works in Xcode 9.4, but when I come to Xcode 10 and recreate my project, I get this Error. My project must add /usr/include/libxml2 , and if I add this, I get a different Error <code>redefinition of madule libxml2</code>. The log is:</p>
  
  <blockquote>
    <p>Add "-Xcc -I$(SDKROOT)/usr/include/libxml2" to OTHER_SWIFT_FLAGS in
    Xcode project.</p>
  </blockquote>
  
  <p>If I add "-Xcc -I$(SDKROOT)/usr/include/libxml2", there is the following error:</p>
  
  <blockquote>
    <p>:0: error: unknown argument: '-Xcc
    -I/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator12.0.sdk/usr/include/libxml2'
    Command CompileSwiftSources failed with a nonzero exit code</p>
  </blockquote>
  
  <p>What can I do?</p>