title: Swift compiler segmentation fault when building
body: <p>Adding a (convenient) computed <code>height</code> property to <code>UIView</code> in my <code>UIViewExtension.swift</code> file is causing the Swift compiler to segfault... What could possibly be going wrong here?</p>
  <pre><code>0  swift                    0x00000001061e5608 llvm::sys::PrintStackTrace(__sFILE*) + 40
  1  swift                    0x00000001061e5af4 SignalHandler(int) + 452
  2  libsystem_platform.dylib 0x00007fff894da5aa _sigtramp + 26
  3  libsystem_platform.dylib 0xb03939841e997c88 _sigtramp + 2504775416
  4  swift                    0x00000001064c8bb9 swift::NominalTypeDecl::getMembers(bool) const + 41
  5  swift                    0x00000001055efab9 swift::irgen::ClassMetadataLayout&lt;(anonymous namespace)::FindClassMethodIndex&gt;::addClassMembers(swift::ClassDecl*) + 329
  6  swift                    0x00000001055e97b2 swift::irgen::emitVirtualMethodValue(swift::irgen::IRGenFunction&amp;, llvm::Value*, swift::SILType, swift::SILDeclRef, swift::CanTypeWrapper&lt;swift::SILFunctionType&gt;, swift::ResilienceExpansion) + 434
  7  swift                    0x00000001056550d3 swift::SILVisitor&lt;(anonymous namespace)::IRGenSILFunction, void&gt;::visit(swift::ValueBase*) + 42611
  8  swift                    0x000000010564a266 swift::irgen::IRGenModule::emitSILFunction(swift::SILFunction*) + 8678
  9  swift                    0x00000001055cb6f8 swift::irgen::IRGenModule::emitGlobalTopLevel() + 184
  10 swift                    0x00000001056376e3 performIRGeneration(swift::IRGenOptions&amp;, swift::Module*, swift::SILModule*, llvm::StringRef, llvm::LLVMContext&amp;, swift::SourceFile*, unsigned int) + 1859
  11 swift                    0x0000000105638033 swift::performIRGeneration(swift::IRGenOptions&amp;, swift::SourceFile&amp;, swift::SILModule*, llvm::StringRef, llvm::LLVMContext&amp;, unsigned int) + 51
  12 swift                    0x00000001055aa65a frontend_main(llvm::ArrayRef&lt;char const*&gt;, char const*, void*) + 4842
  13 swift                    0x00000001055a935d main + 1533
  14 libdyld.dylib            0x00007fff8a82e5fd start + 1
  </code></pre>
  <p> </p>
  <pre><code>1.  While emitting IR SIL function @_TFCSo6UIViewg6heightSd for 'anonname=0x7ff422892fd0' at &lt;path redacted&gt;/UIViewExtension.swift:60:5
  &lt;unknown&gt;:0: error: unable to execute command: Segmentation fault: 11
  &lt;unknown&gt;:0: error: swift frontend command failed due to signal (use -v to see invocation)
  Command /Applications/Xcode6-Beta.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swift failed with exit code 254
  </code></pre>
  <p>If more information is needed to crack this, just comment. Thanks!</p>
  <h3>Edit:</h3>
  <p>Here's a related .xcodeproj that returns this question's compiler error. <a href="http://www.mediafire.com/download/9ic636luugmo6jd/SwiftCompilerSegFaultExample.rar" rel="noreferrer"><strong>Download here</strong></a></p>