diff --git a/lib/Basic/Diagnostic.cpp b/lib/Basic/Diagnostic.cpp
index 7601d49..e8cd218 100644
--- a/lib/Basic/Diagnostic.cpp
+++ b/lib/Basic/Diagnostic.cpp
@@ -175,7 +175,7 @@
   // after the previous one.
   if ((Loc.isValid() && LastStateChangePos.isInvalid()) ||
       LastStateChangePos.isBeforeInTranslationUnitThan(Loc)) {
-    // A diagnostic pragma occured, create a new DiagState initialized with
+    // A diagnostic pragma occurred, create a new DiagState initialized with
     // the current one and a new DiagStatePoint to record at which location
     // the new state became active.
     DiagStates.push_back(*GetCurDiagState());
diff --git a/lib/Basic/SourceManager.cpp b/lib/Basic/SourceManager.cpp
index 8262feb..d73a0af 100644
--- a/lib/Basic/SourceManager.cpp
+++ b/lib/Basic/SourceManager.cpp
@@ -70,7 +70,7 @@
                                                   SourceLocation Loc,
                                                   bool *Invalid) const {
   // Lazily create the Buffer for ContentCaches that wrap files.  If we already
-  // computed it, jsut return what we have.
+  // computed it, just return what we have.
   if (Buffer.getPointer() || ContentsEntry == 0) {
     if (Invalid)
       *Invalid = isBufferInvalid();
@@ -1388,7 +1388,7 @@
   while (!MoveUpIncludeHierarchy(LOffs, *this)) /*empty*/;
   while (!MoveUpIncludeHierarchy(ROffs, *this)) /*empty*/;
   
-  // If exactly one location is a memory buffer, assume it preceeds the other.
+  // If exactly one location is a memory buffer, assume it precedes the other.
   
   // Strip off macro instantation locations, going up to the top-level File
   // SLocEntry.
diff --git a/lib/Basic/TargetInfo.cpp b/lib/Basic/TargetInfo.cpp
index 078452e..dcf0cb4 100644
--- a/lib/Basic/TargetInfo.cpp
+++ b/lib/Basic/TargetInfo.cpp
@@ -432,7 +432,7 @@
     case ',': // multiple alternative constraint.  Ignore comma.
       break;
     case '?': // Disparage slightly code.
-    case '!': // Disparage severly.
+    case '!': // Disparage severely.
       break;  // Pass them.
     }