Convert assert(0) to llvm_unreachable

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@149967 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCDisassembler/EDMain.cpp b/lib/MC/MCDisassembler/EDMain.cpp
index 3fd355b..c658717 100644
--- a/lib/MC/MCDisassembler/EDMain.cpp
+++ b/lib/MC/MCDisassembler/EDMain.cpp
@@ -23,7 +23,7 @@
                       EDAssemblySyntax_t syntax) {
   EDDisassembler::AssemblySyntax Syntax;
   switch (syntax) {
-  default: assert(0 && "Unknown assembly syntax!");
+  default: llvm_unreachable("Unknown assembly syntax!");
   case kEDAssemblySyntaxX86Intel:
     Syntax = EDDisassembler::kEDAssemblySyntaxX86Intel;
     break;