From 51ff0628073e7c547b42f9c5705505e2ce4536a0 Mon Sep 17 00:00:00 2001
From: Malte Stellmacher <malte.stellmacher@student.hpi.de>
Date: Mon, 5 Feb 2024 18:26:47 +0100
Subject: [PATCH] Fix null libraries not entered into map

---
 .../nodes/plugins/ffi/PrimExternalCallNode.java             | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/de.hpi.swa.trufflesqueak/src/de/hpi/swa/trufflesqueak/nodes/plugins/ffi/PrimExternalCallNode.java b/src/de.hpi.swa.trufflesqueak/src/de/hpi/swa/trufflesqueak/nodes/plugins/ffi/PrimExternalCallNode.java
index 368c2131c..eb9779842 100644
--- a/src/de.hpi.swa.trufflesqueak/src/de/hpi/swa/trufflesqueak/nodes/plugins/ffi/PrimExternalCallNode.java
+++ b/src/de.hpi.swa.trufflesqueak/src/de/hpi/swa/trufflesqueak/nodes/plugins/ffi/PrimExternalCallNode.java
@@ -46,6 +46,10 @@ public PrimExternalCallNode(final Object moduleLibrary, final InteropLibrary mod
     public static PrimExternalCallNode load(final String moduleName, final String functionName, final int numReceiverAndArguments) {
         final SqueakImageContext context = SqueakImageContext.getSlow();
         final Object moduleLibrary = loadedLibraries.computeIfAbsent(moduleName, (String s) -> {
+            if (loadedLibraries.containsKey(moduleName)) {
+                // if moduleName was associated with null
+                return null;
+            }
             final Object library;
             try {
                 library = NFIUtils.loadLibrary(context, moduleName, "{ setInterpreter(POINTER):SINT64; }");
@@ -71,6 +75,8 @@ public static PrimExternalCallNode load(final String moduleName, final String fu
             }
             return library;
         });
+        // computeIfAbsent would not put null value
+        loadedLibraries.putIfAbsent(moduleName, moduleLibrary);
         if (moduleLibrary == null) {
             // module not found
             return null;