diff --git a/include/clang/AST/ASTDiagnostic.h b/include/clang/AST/ASTDiagnostic.h
index b005711..6e36372 100644
--- a/include/clang/AST/ASTDiagnostic.h
+++ b/include/clang/AST/ASTDiagnostic.h
@@ -16,7 +16,7 @@
   namespace diag {
     enum {
 #define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,\
-             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY,BRIEF,FULL) ENUM,
+             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY) ENUM,
 #define ASTSTART
 #include "clang/Basic/DiagnosticASTKinds.inc"
 #undef DIAG
diff --git a/include/clang/Analysis/AnalysisDiagnostic.h b/include/clang/Analysis/AnalysisDiagnostic.h
index 16d31b4..d4e1f5f 100644
--- a/include/clang/Analysis/AnalysisDiagnostic.h
+++ b/include/clang/Analysis/AnalysisDiagnostic.h
@@ -16,7 +16,7 @@
   namespace diag {
     enum {
 #define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,\
-             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY,BRIEF,FULL) ENUM,
+             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY) ENUM,
 #define ANALYSISSTART
 #include "clang/Basic/DiagnosticAnalysisKinds.inc"
 #undef DIAG
diff --git a/include/clang/Basic/Diagnostic.td b/include/clang/Basic/Diagnostic.td
index 068cf08..109cd08 100644
--- a/include/clang/Basic/Diagnostic.td
+++ b/include/clang/Basic/Diagnostic.td
@@ -62,8 +62,6 @@
   DiagMapping DefaultMapping = defaultmapping;
   DiagGroup   Group;
   string      CategoryName = "";
-  string      Brief = "";
-  string      Explanation = "";
 }
 
 class Error<string str>     : Diagnostic<str, CLASS_ERROR, MAP_ERROR>;
@@ -87,12 +85,6 @@
 class NoSFINAE { bit SFINAE = 0; }
 class AccessControl { bit AccessControl = 1; }
 
-class Brief<string str> { string Brief = str; }
-class FullExplanation<string brief, string full> {
-  string Brief = brief;
-  string Explanation = full;
-}
-
 // Definitions for Diagnostics.
 include "DiagnosticASTKinds.td"
 include "DiagnosticAnalysisKinds.td"
diff --git a/include/clang/Basic/DiagnosticIDs.h b/include/clang/Basic/DiagnosticIDs.h
index 40fc3a9..b49a4f8 100644
--- a/include/clang/Basic/DiagnosticIDs.h
+++ b/include/clang/Basic/DiagnosticIDs.h
@@ -50,7 +50,7 @@
     // Get typedefs for common diagnostics.
     enum {
 #define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,\
-             SFINAE,ACCESS,CATEGORY,NOWERROR,SHOWINSYSHEADER,BRIEF,FULL) ENUM,
+             SFINAE,ACCESS,CATEGORY,NOWERROR,SHOWINSYSHEADER) ENUM,
 #include "clang/Basic/DiagnosticCommonKinds.inc"
       NUM_BUILTIN_COMMON_DIAGNOSTICS
 #undef DIAG
@@ -229,14 +229,6 @@
   /// getIdFromName - Given a diagnostic name, return its ID, or 0
   static unsigned getIdFromName(StringRef Name);
   
-  /// getBriefExplanation - Given a diagnostic ID, return a brief explanation
-  /// of the issue
-  static StringRef getBriefExplanation(unsigned DiagID);
-
-  /// getFullExplanation - Given a diagnostic ID, return a full explanation
-  /// of the issue
-  static StringRef getFullExplanation(unsigned DiagID);
-  
   /// Iterator class used for traversing all statically declared
   /// diagnostics.
   class diag_iterator {
diff --git a/include/clang/Driver/DriverDiagnostic.h b/include/clang/Driver/DriverDiagnostic.h
index 844f918..ea7b52f 100644
--- a/include/clang/Driver/DriverDiagnostic.h
+++ b/include/clang/Driver/DriverDiagnostic.h
@@ -16,7 +16,7 @@
   namespace diag {
     enum {
 #define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,\
-             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY,BRIEF,FULL) ENUM,
+             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY) ENUM,
 #define DRIVERSTART
 #include "clang/Basic/DiagnosticDriverKinds.inc"
 #undef DIAG
diff --git a/include/clang/Frontend/FrontendDiagnostic.h b/include/clang/Frontend/FrontendDiagnostic.h
index 21cd2c6..0b05b74 100644
--- a/include/clang/Frontend/FrontendDiagnostic.h
+++ b/include/clang/Frontend/FrontendDiagnostic.h
@@ -16,7 +16,7 @@
   namespace diag {
     enum {
 #define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,\
-             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY,BRIEF,FULL) ENUM,
+             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY) ENUM,
 #define FRONTENDSTART
 #include "clang/Basic/DiagnosticFrontendKinds.inc"
 #undef DIAG
diff --git a/include/clang/Lex/LexDiagnostic.h b/include/clang/Lex/LexDiagnostic.h
index f454e23..41b9396 100644
--- a/include/clang/Lex/LexDiagnostic.h
+++ b/include/clang/Lex/LexDiagnostic.h
@@ -16,7 +16,7 @@
   namespace diag {
     enum {
 #define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,\
-             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY,BRIEF,FULL) ENUM,
+             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY) ENUM,
 #define LEXSTART
 #include "clang/Basic/DiagnosticLexKinds.inc"
 #undef DIAG
diff --git a/include/clang/Parse/ParseDiagnostic.h b/include/clang/Parse/ParseDiagnostic.h
index 0e76c61..0d47292 100644
--- a/include/clang/Parse/ParseDiagnostic.h
+++ b/include/clang/Parse/ParseDiagnostic.h
@@ -16,7 +16,7 @@
   namespace diag {
     enum {
 #define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,\
-             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY,BRIEF,FULL) ENUM,
+             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY) ENUM,
 #define PARSESTART
 #include "clang/Basic/DiagnosticParseKinds.inc"
 #undef DIAG
diff --git a/include/clang/Sema/SemaDiagnostic.h b/include/clang/Sema/SemaDiagnostic.h
index 2c4bf4b..9605bf8 100644
--- a/include/clang/Sema/SemaDiagnostic.h
+++ b/include/clang/Sema/SemaDiagnostic.h
@@ -16,7 +16,7 @@
   namespace diag {
     enum {
 #define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,\
-             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY,BRIEF,FULL) ENUM,
+             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY) ENUM,
 #define SEMASTART
 #include "clang/Basic/DiagnosticSemaKinds.inc"
 #undef DIAG
diff --git a/include/clang/Serialization/SerializationDiagnostic.h b/include/clang/Serialization/SerializationDiagnostic.h
index 796a328..e63f814 100644
--- a/include/clang/Serialization/SerializationDiagnostic.h
+++ b/include/clang/Serialization/SerializationDiagnostic.h
@@ -16,7 +16,7 @@
   namespace diag {
     enum {
 #define DIAG(ENUM,FLAGS,DEFAULT_MAPPING,DESC,GROUP,\
-             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY,BRIEF,FULL) ENUM,
+             SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,CATEGORY) ENUM,
 #define SERIALIZATIONSTART
 #include "clang/Basic/DiagnosticSerializationKinds.inc"
 #undef DIAG
diff --git a/lib/Basic/DiagnosticIDs.cpp b/lib/Basic/DiagnosticIDs.cpp
index 1e8f44d..6c15e25 100644
--- a/lib/Basic/DiagnosticIDs.cpp
+++ b/lib/Basic/DiagnosticIDs.cpp
@@ -56,15 +56,11 @@
   uint8_t  OptionGroupLen;
 
   uint16_t DescriptionLen;
-  uint16_t BriefExplanationLen;
-  uint16_t FullExplanationLen;
 
   const char *NameStr;
   const char *OptionGroupStr;
 
   const char *DescriptionStr;
-  const char *BriefExplanationStr;
-  const char *FullExplanationStr;
 
   StringRef getName() const {
     return StringRef(NameStr, NameLen);
@@ -76,12 +72,6 @@
   StringRef getDescription() const {
     return StringRef(DescriptionStr, DescriptionLen);
   }
-  StringRef getBriefExplanation() const {
-    return StringRef(BriefExplanationStr, BriefExplanationLen);
-  }
-  StringRef getFullExplanation() const {
-    return StringRef(FullExplanationStr, FullExplanationLen);
-  }
 
   bool operator<(const StaticDiagInfoRec &RHS) const {
     return DiagID < RHS.DiagID;
@@ -120,13 +110,12 @@
 static const StaticDiagInfoRec StaticDiagInfo[] = {
 #define DIAG(ENUM,CLASS,DEFAULT_MAPPING,DESC,GROUP,               \
              SFINAE,ACCESS,NOWERROR,SHOWINSYSHEADER,              \
-             CATEGORY,BRIEF,FULL)                                 \
+             CATEGORY)                                            \
   { diag::ENUM, DEFAULT_MAPPING, CLASS, SFINAE, ACCESS,           \
     NOWERROR, SHOWINSYSHEADER, CATEGORY,                          \
     STR_SIZE(#ENUM, uint8_t), STR_SIZE(GROUP, uint8_t),           \
-    STR_SIZE(DESC, uint16_t), STR_SIZE(BRIEF, uint16_t),          \
-    STR_SIZE(FULL, uint16_t),                                     \
-    #ENUM, GROUP, DESC, BRIEF, FULL },
+    STR_SIZE(DESC, uint16_t),                                     \
+    #ENUM, GROUP, DESC },
 #include "clang/Basic/DiagnosticCommonKinds.inc"
 #include "clang/Basic/DiagnosticDriverKinds.inc"
 #include "clang/Basic/DiagnosticFrontendKinds.inc"
@@ -137,7 +126,7 @@
 #include "clang/Basic/DiagnosticSemaKinds.inc"
 #include "clang/Basic/DiagnosticAnalysisKinds.inc"
 #undef DIAG
-  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
 };
 
 static const unsigned StaticDiagInfoSize =
@@ -175,7 +164,7 @@
 
   // Search the diagnostic table with a binary search.
   StaticDiagInfoRec Find = { static_cast<unsigned short>(DiagID),
-                             0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
+                             0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
 
   const StaticDiagInfoRec *Found =
     std::lower_bound(StaticDiagInfo, StaticDiagInfo + StaticDiagInfoSize, Find);
@@ -325,22 +314,6 @@
   return Found->DiagID;
 }
 
-/// getBriefExplanation - Given a diagnostic ID, return a brief explanation
-/// of the issue
-StringRef DiagnosticIDs::getBriefExplanation(unsigned DiagID) {
-  if (const StaticDiagInfoRec *Info = GetDiagInfo(DiagID))
-    return Info->getBriefExplanation();
-  return StringRef();
-}
-
-/// getFullExplanation - Given a diagnostic ID, return a full explanation
-/// of the issue
-StringRef DiagnosticIDs::getFullExplanation(unsigned DiagID) {
-  if (const StaticDiagInfoRec *Info = GetDiagInfo(DiagID))
-    return Info->getFullExplanation();
-  return StringRef();
-}
-
 /// getBuiltinDiagClass - Return the class field of the diagnostic.
 ///
 static unsigned getBuiltinDiagClass(unsigned DiagID) {
diff --git a/utils/TableGen/ClangDiagnosticsEmitter.cpp b/utils/TableGen/ClangDiagnosticsEmitter.cpp
index 8240360..c754ef1 100644
--- a/utils/TableGen/ClangDiagnosticsEmitter.cpp
+++ b/utils/TableGen/ClangDiagnosticsEmitter.cpp
@@ -194,14 +194,6 @@
   
     // Category number.
     OS << ", " << CategoryIDs.getID(getDiagnosticCategory(&R, DGParentMap));
-
-    // Brief
-    OS << ", \"";
-    OS.write_escaped(R.getValueAsString("Brief")) << '"';
-
-    // Explanation 
-    OS << ", \"";
-    OS.write_escaped(R.getValueAsString("Explanation")) << '"';
     OS << ")\n";
   }
 }