diff --git a/llvm/lib/CodeGen/MachineModuleInfo.cpp b/llvm/lib/CodeGen/MachineModuleInfo.cpp
--- a/llvm/lib/CodeGen/MachineModuleInfo.cpp
+++ b/llvm/lib/CodeGen/MachineModuleInfo.cpp
@@ -196,6 +196,7 @@
 void MachineModuleInfo::initialize() {
   ObjFileMMI = nullptr;
   CurCallSite = 0;
+  NextFnNum = 0;
   UsesMSVCFloatingPoint = UsesMorestackAddr = false;
   HasSplitStack = HasNosplitStack = false;
   AddrLabelSymbols = nullptr;