Index: source/Plugins/ExpressionParser/Clang/ClangHost.cpp
===================================================================
--- source/Plugins/ExpressionParser/Clang/ClangHost.cpp
+++ source/Plugins/ExpressionParser/Clang/ClangHost.cpp
@@ -45,6 +45,8 @@
   std::string raw_path = lldb_shlib_spec.GetPath();
   llvm::StringRef parent_dir = llvm::sys::path::parent_path(raw_path);
 
+  // LLVM.org's build of LLDB uses the clang resource directory placed in
+  // $install_dir/lib/clang/$clang_version
   llvm::SmallString<256> clang_dir(parent_dir);
   llvm::SmallString<32> relative_path;
   llvm::sys::path::append(relative_path,
@@ -58,6 +60,18 @@
     return true;
   }
 
+  // swift-lldb uses the clang resource directory copied from swift, which by
+  // default is placed in $install_dir/lib/lldb/clang
+  clang_dir = parent_dir;
+  relative_path.clear();
+  llvm::sys::path::append(relative_path, "lib", "lldb", "clang");
+  llvm::sys::path::append(clang_dir, relative_path);
+  if (!verify || VerifyClangPath(clang_dir)) {
+    file_spec.GetDirectory().SetString(clang_dir);
+    FileSystem::Instance().Resolve(file_spec);
+    return true;
+  }
+
   return HostInfo::ComputePathRelativeToLibrary(file_spec, relative_path);
 }