diff --git a/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp b/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp
index 4d567c89a55..644eaadef0e 100644
--- a/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfAccelTable.cpp
@@ -24,7 +24,6 @@ using namespace llvm;
 
 const char *DwarfAccelTable::Atom::AtomTypeString(enum AtomType AT) {
   switch (AT) {
-  default: llvm_unreachable("invalid AtomType!");
   case eAtomTypeNULL: return "eAtomTypeNULL";
   case eAtomTypeDIEOffset: return "eAtomTypeDIEOffset";
   case eAtomTypeCUOffset: return "eAtomTypeCUOffset";
@@ -32,6 +31,7 @@ const char *DwarfAccelTable::Atom::AtomTypeString(enum AtomType AT) {
   case eAtomTypeNameFlags: return "eAtomTypeNameFlags";
   case eAtomTypeTypeFlags: return "eAtomTypeTypeFlags";
   } 
+  llvm_unreachable("invalid AtomType!");
 }
 
 // The general case would need to have a less hard coded size for the
diff --git a/lib/Support/CommandLine.cpp b/lib/Support/CommandLine.cpp
index ce9344954bc..d1f9fad8dd4 100644
--- a/lib/Support/CommandLine.cpp
+++ b/lib/Support/CommandLine.cpp
@@ -292,12 +292,6 @@ static inline bool ProvideOption(Option *Handler, StringRef ArgName,
     break;
   case ValueOptional:
     break;
-
-  default:
-    errs() << ProgramName
-         << ": Bad ValueMask flag! CommandLine usage error:"
-         << Handler->getValueExpectedFlag() << "\n";
-    llvm_unreachable(0);
   }
 
   // If this isn't a multi-arg option, just run the handler.
diff --git a/lib/Support/SourceMgr.cpp b/lib/Support/SourceMgr.cpp
index 5a6090d05e3..bbe36b260b9 100644
--- a/lib/Support/SourceMgr.cpp
+++ b/lib/Support/SourceMgr.cpp
@@ -244,7 +244,6 @@ void SMDiagnostic::print(const char *ProgName, raw_ostream &S) const {
   }
 
   switch (Kind) {
-  default: assert(0 && "Unknown diagnostic kind");
   case SourceMgr::DK_Error: S << "error: "; break;
   case SourceMgr::DK_Warning: S << "warning: "; break;
   case SourceMgr::DK_Note: S << "note: "; break;
diff --git a/lib/TableGen/Record.cpp b/lib/TableGen/Record.cpp
index 25ff0629072..bdd6e1562b9 100644
--- a/lib/TableGen/Record.cpp
+++ b/lib/TableGen/Record.cpp
@@ -727,7 +727,6 @@ UnOpInit *UnOpInit::get(UnaryOp opc, Init *lhs, RecTy *Type) {
 
 Init *UnOpInit::Fold(Record *CurRec, MultiClass *CurMultiClass) const {
   switch (getOpcode()) {
-  default: assert(0 && "Unknown unop");
   case CAST: {
     if (getType()->getAsString() == "string") {
       StringInit *LHSs = dynamic_cast<StringInit*>(LHS);
@@ -880,7 +879,6 @@ BinOpInit *BinOpInit::get(BinaryOp opc, Init *lhs,
 
 Init *BinOpInit::Fold(Record *CurRec, MultiClass *CurMultiClass) const {
   switch (getOpcode()) {
-  default: assert(0 && "Unknown binop");
   case CONCAT: {
     DagInit *LHSs = dynamic_cast<DagInit*>(LHS);
     DagInit *RHSs = dynamic_cast<DagInit*>(RHS);
@@ -1129,7 +1127,6 @@ static Init *ForeachHelper(Init *LHS, Init *MHS, Init *RHS, RecTy *Type,
 
 Init *TernOpInit::Fold(Record *CurRec, MultiClass *CurMultiClass) const {
   switch (getOpcode()) {
-  default: assert(0 && "Unknown binop");
   case SUBST: {
     DefInit *LHSd = dynamic_cast<DefInit*>(LHS);
     VarInit *LHSv = dynamic_cast<VarInit*>(LHS);
diff --git a/lib/Target/ARM/ARMConstantPoolValue.cpp b/lib/Target/ARM/ARMConstantPoolValue.cpp
index 9576283553b..78dc78f9f33 100644
--- a/lib/Target/ARM/ARMConstantPoolValue.cpp
+++ b/lib/Target/ARM/ARMConstantPoolValue.cpp
@@ -48,7 +48,6 @@ ARMConstantPoolValue::~ARMConstantPoolValue() {}
 
 const char *ARMConstantPoolValue::getModifierText() const {
   switch (Modifier) {
-  default: llvm_unreachable("Unknown modifier!");
     // FIXME: Are these case sensitive? It'd be nice to lower-case all the
     // strings if that's legal.
   case ARMCP::no_modifier: return "none";
@@ -58,6 +57,7 @@ const char *ARMConstantPoolValue::getModifierText() const {
   case ARMCP::GOTTPOFF:    return "gottpoff";
   case ARMCP::TPOFF:       return "tpoff";
   }
+  llvm_unreachable("Unknown modifier!");
 }
 
 int ARMConstantPoolValue::getExistingMachineCPValue(MachineConstantPool *CP,
diff --git a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
index 7e5e770a38b..021803de711 100644
--- a/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
+++ b/lib/Target/ARM/AsmParser/ARMAsmParser.cpp
@@ -2866,8 +2866,6 @@ parseVectorList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
       if (Res != MatchOperand_Success)
         return Res;
       switch (LaneKind) {
-      default:
-        assert(0 && "unexpected lane kind!");
       case NoLanes:
         E = Parser.getTok().getLoc();
         Operands.push_back(ARMOperand::CreateVectorList(Reg, 1, false, S, E));
@@ -2891,8 +2889,6 @@ parseVectorList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
       if (Res != MatchOperand_Success)
         return Res;
       switch (LaneKind) {
-      default:
-        assert(0 && "unexpected lane kind!");
       case NoLanes:
         E = Parser.getTok().getLoc();
         Operands.push_back(ARMOperand::CreateVectorList(Reg, 2, false, S, E));
@@ -3063,8 +3059,6 @@ parseVectorList(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
   Parser.Lex(); // Eat '}' token.
 
   switch (LaneKind) {
-  default:
-    assert(0 && "unexpected lane kind in register list.");
   case NoLanes:
     Operands.push_back(ARMOperand::CreateVectorList(FirstReg, Count,
                                                     (Spacing == 2), S, E));
diff --git a/lib/Target/Mips/MipsJITInfo.cpp b/lib/Target/Mips/MipsJITInfo.cpp
index 27d5918c8b6..b15d290d6ca 100644
--- a/lib/Target/Mips/MipsJITInfo.cpp
+++ b/lib/Target/Mips/MipsJITInfo.cpp
@@ -228,9 +228,6 @@ void MipsJITInfo::relocate(void *Function, MachineRelocation *MR,
       *((unsigned*) RelocPos) |= (unsigned) ResultPtr;
       break;
     }
-
-    default:
-      llvm_unreachable("ERROR: Unknown Mips relocation.");
     }
   }
 }
diff --git a/lib/VMCore/Core.cpp b/lib/VMCore/Core.cpp
index 69fb75f01c7..35315df220f 100644
--- a/lib/VMCore/Core.cpp
+++ b/lib/VMCore/Core.cpp
@@ -690,12 +690,11 @@ static LLVMOpcode map_to_llvmopcode(int opcode)
 static int map_from_llvmopcode(LLVMOpcode code)
 {
     switch (code) {
-      default:
-        assert(0 && "Unhandled Opcode.");
 #define HANDLE_INST(num, opc, clas) case LLVM##opc: return num;
 #include "llvm/Instruction.def"
 #undef HANDLE_INST
     }
+    llvm_unreachable("Unhandled Opcode.");
 }
 
 /*--.. Constant expressions ................................................--*/
diff --git a/utils/TableGen/TableGen.cpp b/utils/TableGen/TableGen.cpp
index 2b1c89de8c1..8c41358e3d8 100644
--- a/utils/TableGen/TableGen.cpp
+++ b/utils/TableGen/TableGen.cpp
@@ -178,9 +178,6 @@ namespace {
         }
         break;
       }
-      default:
-        assert(1 && "Invalid Action");
-        return true;
       }
   
       return false;