Index: lib/MC/MCParser/AsmParser.cpp
===================================================================
--- lib/MC/MCParser/AsmParser.cpp
+++ lib/MC/MCParser/AsmParser.cpp
@@ -608,6 +608,10 @@
 AsmParser::~AsmParser() {
   assert((HadError || ActiveMacros.empty()) &&
          "Unexpected active macro instantiation!");
+
+  // Restore the saved diagnostics handler and context for use during
+  // finalization.
+  SrcMgr.setDiagHandler(SavedDiagHandler, SavedDiagContext);
 }
 
 void AsmParser::printMacroInstantiations() {