diff --git a/llvm/lib/IR/Mangler.cpp b/llvm/lib/IR/Mangler.cpp
--- a/llvm/lib/IR/Mangler.cpp
+++ b/llvm/lib/IR/Mangler.cpp
@@ -186,7 +186,7 @@
 
 // Check if the name needs quotes to be safe for the linker to interpret.
 static bool canBeUnquotedInDirective(char C) {
-  return isAlnum(C) || C == '_' || C == '$' || C == '.' || C == '@';
+  return isAlnum(C) || C == '_' || C == '$' || C == '@';
 }
 
 static bool canBeUnquotedInDirective(StringRef Name) {