Fix 'not all control paths return a value' MSVC warnings. NFCI.

llvm-svn: 331753

clang/lib/AST/ExprConstant.cpp

@@ -8616,6 +8616,7 @@ EvaluateComparisonBinaryOperator(EvalInfo &Info, const BinaryOperator *E,
       case APFloat::cmpUnordered:
         return CCR::Unordered;
       }
+      llvm_unreachable("Unrecognised APFloat::cmpResult enum");
     };
     return Success(GetCmpRes(), E);
   }

clang/lib/CodeGen/CGExprAgg.cpp

@@ -920,6 +920,7 @@ static llvm::Value *EmitCompare(CGBuilderTy &Builder, CodeGenFunction &CGF,
     case CK_Equal:
       return {"cmp.eq", FI::FCMP_OEQ, II::ICMP_EQ, II::ICMP_EQ};
     }
+    llvm_unreachable("Unrecognised CompareKind enum");
   }();
 
   if (ArgTy->hasFloatingRepresentation())