diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 800f64c..17ce614 100644
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -24,6 +24,7 @@
 #include "clang/AST/StmtCXX.h"
 #include "clang/AST/StmtObjC.h"
 #include "clang/Analysis/Analyses/FormatString.h"
+#include "clang/Basic/CharInfo.h"
 #include "clang/Basic/TargetBuiltins.h"
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Lex/Preprocessor.h"
@@ -6172,7 +6173,7 @@
     return false;
 
   if (str.empty()) return true;
-  return !islower(str.front());
+  return !isLowercase(str.front());
 }
 
 /// Check a message send to see if it's likely to cause a retain cycle.
diff --git a/lib/Sema/SemaDeclAttr.cpp b/lib/Sema/SemaDeclAttr.cpp
index 8aedaf7..4c8d098 100644
--- a/lib/Sema/SemaDeclAttr.cpp
+++ b/lib/Sema/SemaDeclAttr.cpp
@@ -19,6 +19,7 @@
 #include "clang/AST/DeclObjC.h"
 #include "clang/AST/DeclTemplate.h"
 #include "clang/AST/Expr.h"
+#include "clang/Basic/CharInfo.h"
 #include "clang/Basic/SourceManager.h"
 #include "clang/Basic/TargetInfo.h"
 #include "clang/Sema/DeclSpec.h"
@@ -4478,7 +4479,7 @@
           S.Diag(Attr.getLoc(), diag::err_attribute_uuid_malformed_guid);
           return;
         }
-      } else if (!isxdigit(*I)) {
+      } else if (!isHexDigit(*I)) {
         S.Diag(Attr.getLoc(), diag::err_attribute_uuid_malformed_guid);
         return;
       }
diff --git a/lib/Sema/SemaPseudoObject.cpp b/lib/Sema/SemaPseudoObject.cpp
index bf3b82b..5770675 100644
--- a/lib/Sema/SemaPseudoObject.cpp
+++ b/lib/Sema/SemaPseudoObject.cpp
@@ -32,6 +32,7 @@
 
 #include "clang/Sema/SemaInternal.h"
 #include "clang/AST/ExprObjC.h"
+#include "clang/Basic/CharInfo.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Sema/Initialization.h"
 #include "clang/Sema/ScopeInfo.h"
@@ -562,8 +563,9 @@
       if (const ObjCInterfaceDecl *IFace =
           dyn_cast<ObjCInterfaceDecl>(setter->getDeclContext())) {
         const StringRef thisPropertyName(prop->getName());
+        // Try flipping the case of the first character.
         char front = thisPropertyName.front();
-        front = islower(front) ? toupper(front) : tolower(front);
+        front = isLowercase(front) ? toUppercase(front) : toLowercase(front);
         SmallString<100> PropertyName = thisPropertyName;
         PropertyName[0] = front;
         IdentifierInfo *AltMember = &S.PP.getIdentifierTable().get(PropertyName);