From 090e7b9faa1e3baf6198c0999759ede2471a3ff0 Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Wed, 19 Jun 2024 10:51:15 -0700
Subject: [PATCH] Fix crash in isSourceFileDefaultLibrary for vscode benchmark

---
 src/compiler/program.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/program.ts b/src/compiler/program.ts
index f41919a28ac44..807e3bb8c5091 100644
--- a/src/compiler/program.ts
+++ b/src/compiler/program.ts
@@ -2788,7 +2788,7 @@ export function createProgram(rootNamesOrOptions: readonly string[] | CreateProg
             return equalityComparer(file.fileName, getDefaultLibraryFileName());
         }
         else {
-            return some(options.lib, libFileName => equalityComparer(file.fileName, resolvedLibReferences!.get(libFileName)!.actual));
+            return some(options.lib, libFileName => resolvedLibReferences!.has(libFileName) && equalityComparer(file.fileName, resolvedLibReferences!.get(libFileName)!.actual));
         }
     }