diff --git a/llvm/lib/Passes/StandardInstrumentations.cpp b/llvm/lib/Passes/StandardInstrumentations.cpp
--- a/llvm/lib/Passes/StandardInstrumentations.cpp
+++ b/llvm/lib/Passes/StandardInstrumentations.cpp
@@ -647,13 +647,12 @@
 
   ChangedIRData::report(
       Before, After, [&](const ChangedFuncData *B, const ChangedFuncData *A) {
+        assert((B || A) && "Both functions cannot be missing.");
         ChangedFuncData Missing;
         if (!B)
           B = &Missing;
         else if (!A)
           A = &Missing;
-        assert(B != &Missing && A != &Missing &&
-               "Both functions cannot be missing.");
         handleFunctionCompare(Name, Prefix, PassID, true, *B, *A);
       });
 }
diff --git a/llvm/test/Other/ChangePrinters/print-changed-D107989.ll b/llvm/test/Other/ChangePrinters/print-changed-D107989.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Other/ChangePrinters/print-changed-D107989.ll
@@ -0,0 +1,13 @@
+; D107989 This triggered an assert
+
+; RUN: opt  -passes=globalopt < %s -disable-output -print-changed=diff-quiet
+
+define signext i32 @main()  {
+entry:
+  ret i32 0
+}
+
+define internal void @f() {
+entry:
+  ret void
+}