diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index cd7ada607f9..0ddea8baf08 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -6683,7 +6683,6 @@ module ts {
                 return;
             }
 
-            var symbol = getSymbolOfNode(signatureDeclarationNode);
             // TypeScript 1.0 spec (April 2014): 3.7.2.4
             // Every specialized call or construct signature in an object type must be assignable
             // to at least one non-specialized call or construct signature in the same object type
@@ -8811,7 +8810,6 @@ module ts {
                 // parent is not source file or it is not reference to internal module
                 return false;
             }
-            var symbol = getSymbolOfNode(node);
             return isImportResolvedToValue(getSymbolOfNode(node));
         }
 
diff --git a/src/harness/compilerRunner.ts b/src/harness/compilerRunner.ts
index f23647024f9..7045a1196d0 100644
--- a/src/harness/compilerRunner.ts
+++ b/src/harness/compilerRunner.ts
@@ -285,12 +285,10 @@ class CompilerBaselineRunner extends RunnerBase {
                             typeLines.push('=== ' + file.unitName + ' ===\r\n');
                             for (var i = 0; i < codeLines.length; i++) {
                                 var currentCodeLine = codeLines[i];
-                                var lastLine = typeLines[typeLines.length];
                                 typeLines.push(currentCodeLine + '\r\n');
                                 if (typeMap[file.unitName]) {
                                     var typeInfo = typeMap[file.unitName][i];
                                     if (typeInfo) {
-                                        var leadingSpaces = '';
                                         typeInfo.forEach(ty => {
                                             typeLines.push('>' + ty + '\r\n');
                                         });
diff --git a/src/services/services.ts b/src/services/services.ts
index 9a689a7ff33..27e4f43c0f0 100644
--- a/src/services/services.ts
+++ b/src/services/services.ts
@@ -144,7 +144,7 @@ module ts {
             while (pos < end) {
                 var token = scanner.scan();
                 var textPos = scanner.getTextPos();
-                var node = nodes.push(createNode(token, pos, textPos, NodeFlags.Synthetic, this));
+                nodes.push(createNode(token, pos, textPos, NodeFlags.Synthetic, this));
                 pos = textPos;
             }
             return pos;
@@ -662,8 +662,6 @@ module ts {
         }
     }
 
-    var incrementalParse: IncrementalParse = TypeScript.IncrementalParser.parse;
-
     class SourceFileObject extends NodeObject implements SourceFile {
         public filename: string;
         public text: string;
@@ -3735,9 +3733,6 @@ module ts {
 
                 pushKeywordIf(keywords, switchStatement.getFirstToken(), SyntaxKind.SwitchKeyword);
 
-                // Types of break statements we can grab on to.
-                var breakSearchType = BreakContinueSearchType.All;
-
                 // Go through each clause in the switch statement, collecting the 'case'/'default' keywords.
                 forEach(switchStatement.clauses, clause => {
                     pushKeywordIf(keywords, clause.getFirstToken(), SyntaxKind.CaseKeyword, SyntaxKind.DefaultKeyword);
@@ -4611,7 +4606,6 @@ module ts {
             var targetSourceFile = program.getSourceFile(filename);  // Current selected file to be output
             // If --out flag is not specified, shouldEmitToOwnFile is true. Otherwise shouldEmitToOwnFile is false.
             var shouldEmitToOwnFile = ts.shouldEmitToOwnFile(targetSourceFile, compilerOptions);
-            var emitDeclaration = compilerOptions.declaration;
             var emitOutput: EmitOutput = {
                 outputFiles: [],
                 emitOutputStatus: undefined,