diff --git a/lib/ClangImporter/ClangImporter.cpp b/lib/ClangImporter/ClangImporter.cpp
index a1355d880a5f7..3edabcb5b1a86 100644
--- a/lib/ClangImporter/ClangImporter.cpp
+++ b/lib/ClangImporter/ClangImporter.cpp
@@ -702,8 +702,16 @@ void importer::getNormalInvocationArguments(
         invocationArgStrs.push_back(searchPathOpts.getSDKPath().str());
       } else {
         if (auto sysroot = searchPathOpts.getSysRoot()) {
+          // Both the sdk path and sysroot are provided. Pass along the sysroot
+          // to Clang but also ensure the SDK include path is provided.
           invocationArgStrs.push_back("--sysroot");
           invocationArgStrs.push_back(sysroot->str());
+
+          llvm::SmallString<256> path;
+          path = searchPathOpts.getSDKPath();
+          llvm::sys::path::append(path, "usr", "include");
+          invocationArgStrs.push_back("-isystem");
+          invocationArgStrs.push_back(path.str().str());
         } else {
           invocationArgStrs.push_back("--sysroot");
           invocationArgStrs.push_back(searchPathOpts.getSDKPath().str());