diff --git a/lib/Sema/CSGen.cpp b/lib/Sema/CSGen.cpp
index e4c1e480d5134..e6d2e21b674ba 100644
--- a/lib/Sema/CSGen.cpp
+++ b/lib/Sema/CSGen.cpp
@@ -53,7 +53,7 @@ static ValueDecl *findReferencedDecl(Expr *expr, SourceLoc &loc) {
 }
 
 /// \brief Return 'true' if the decl in question refers to an operator that
-/// could be added to the global scope via a delayed protcol conformance.
+/// could be added to the global scope via a delayed protocol conformance.
 /// Currently, this is only true for '==', which is added via an Equatable
 /// conformance.
 static bool isDelayedOperatorDecl(ValueDecl *vd) {
@@ -337,7 +337,7 @@ namespace {
   /// of the overload set and call arguments.
   ///
   /// \param expr The application.
-  /// \param isFavored Determine wheth the given overload is favored.
+  /// \param isFavored Determine whether the given overload is favored.
   /// \param createReplacements If provided, a function that creates a set of
   /// replacement fallback constraints.
   /// \param mustConsider If provided, a function to detect the presence of
@@ -2664,7 +2664,7 @@ Expr *ConstraintSystem::generateConstraints(Expr *expr) {
   // Remove implicit conversions from the expression.
   expr = expr->walk(SanitizeExpr(getTypeChecker()));
 
-  // Wall the expression to associate labeled argumets.
+  // Wall the expression to associate labeled arguments.
   expr->walk(ArgumentLabelWalker(*this, expr));
 
   // Walk the expression, generating constraints.
@@ -2740,7 +2740,7 @@ class InferUnresolvedMemberConstraintGenerator : public ConstraintGenerator {
       return ConstraintGenerator::visitUnresolvedMemberExpr(Expr);
     }
     // Otherwise, create a type variable saying we know nothing about this expr.
-    assert(!VT && "cannot reassign type viriable.");
+    assert(!VT && "cannot reassign type variable.");
     return VT = createFreeTypeVariableType(Expr);
   }
 
@@ -2750,7 +2750,7 @@ class InferUnresolvedMemberConstraintGenerator : public ConstraintGenerator {
       return ConstraintGenerator::visitParenExpr(Expr);
     }
     // Otherwise, create a type variable saying we know nothing about this expr.
-    assert(!VT && "cannot reassign type viriable.");
+    assert(!VT && "cannot reassign type variable.");
     return VT = createFreeTypeVariableType(Expr);
   }
 
@@ -2760,7 +2760,7 @@ class InferUnresolvedMemberConstraintGenerator : public ConstraintGenerator {
       return ConstraintGenerator::visitTupleExpr(Expr);
     }
     // Otherwise, create a type variable saying we know nothing about this expr.
-    assert(!VT && "cannot reassign type viriable.");
+    assert(!VT && "cannot reassign type variable.");
     return VT = createFreeTypeVariableType(Expr);
   }
 
diff --git a/lib/Sema/TypeCheckDecl.cpp b/lib/Sema/TypeCheckDecl.cpp
index f83bfb31c7b7b..547e92fa264ce 100644
--- a/lib/Sema/TypeCheckDecl.cpp
+++ b/lib/Sema/TypeCheckDecl.cpp
@@ -2930,7 +2930,7 @@ class DeclChecker : public DeclVisitor<DeclChecker> {
 
     if (!IsSecondPass) {
       for (unsigned i = 0, e = PBD->getNumPatternEntries(); i != e; ++i) {
-        // Type check each VarDecl in that his PatternBinding handles.
+        // Type check each VarDecl that this PatternBinding handles.
         visitBoundVars(PBD->getPattern(i));
 
         // If we have a type but no initializer, check whether the type is