diff --git a/src/harness/harness.ts b/src/harness/harness.ts
index 097340082e3..de675948851 100644
--- a/src/harness/harness.ts
+++ b/src/harness/harness.ts
@@ -1424,6 +1424,9 @@ module Harness {
                 return diagnostic.file && diagnostic.file.fileName.indexOf("test262-harness") >= 0;
             });
 
+            // Verify we didn't miss any errors in total
+            assert.equal(totalErrorsReported + numLibraryDiagnostics + numTest262HarnessDiagnostics, diagnostics.length, "total number of errors");
+
             return minimalDiagnosticsToString(diagnostics) +
                 Harness.IO.newLine() + Harness.IO.newLine() + outputLines.join("\r\n");
         }
diff --git a/src/harness/rwcRunner.ts b/src/harness/rwcRunner.ts
index ea6f7b7ebb1..d8b52ec2e39 100644
--- a/src/harness/rwcRunner.ts
+++ b/src/harness/rwcRunner.ts
@@ -65,15 +65,6 @@ module RWC {
                     opts.options.noEmitOnError = false;
                 });
 
-                if (!useCustomLibraryFile) {
-                    let defaultLibPath = ts.sys.resolvePath("built/local/lib.d.ts");
-                    let defaultLib = {
-                        unitName: ts.normalizePath(defaultLibPath),
-                        content: Harness.IO.readFile(defaultLibPath)
-                    };
-                    inputFiles.push(defaultLib);
-                }
-
                 runWithIOLog(ioLog, () => {
                     harnessCompiler.reset();
 
@@ -105,6 +96,9 @@ module RWC {
                                 if (useCustomLibraryFile) {
                                     inputFiles.push(getHarnessCompilerInputUnit(fileRead.path));
                                 }
+                                else {
+                                    inputFiles.push(Harness.getDefaultLibraryFile());
+                                }
                             }
                         }
                     }