From 75570079aeeeeb5fbb8dcc0a147d2e361c2a2ea8 Mon Sep 17 00:00:00 2001
From: AterAnimAvis <AterAnimAvis@users.noreply.github.com>
Date: Mon, 15 Feb 2021 21:16:09 +0000
Subject: [PATCH] Fix: Clear the last error from glfwInit to prevent vanilla
 from throwing an exception later in the chain when glfw errors. (#7587)

---
 .../loading/progress/ClientVisualization.java  | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/fmllauncher/java/net/minecraftforge/fml/loading/progress/ClientVisualization.java b/src/fmllauncher/java/net/minecraftforge/fml/loading/progress/ClientVisualization.java
index faa9055b68..41fecbf35e 100644
--- a/src/fmllauncher/java/net/minecraftforge/fml/loading/progress/ClientVisualization.java
+++ b/src/fmllauncher/java/net/minecraftforge/fml/loading/progress/ClientVisualization.java
@@ -22,6 +22,7 @@ package net.minecraftforge.fml.loading.progress;
 import com.google.common.io.ByteStreams;
 import org.apache.commons.lang3.tuple.Pair;
 import org.apache.logging.log4j.LogManager;
+import org.lwjgl.PointerBuffer;
 import org.lwjgl.glfw.*;
 import org.lwjgl.opengl.GL;
 import org.lwjgl.opengl.GL11;
@@ -38,6 +39,7 @@ import java.nio.Buffer;
 import java.nio.ByteBuffer;
 import java.nio.IntBuffer;
 import java.util.List;
+import java.util.function.BiConsumer;
 import java.util.function.IntConsumer;
 import java.util.function.IntSupplier;
 import java.util.function.LongSupplier;
@@ -75,6 +77,9 @@ class ClientVisualization implements EarlyProgressVisualization.Visualization {
             LogManager.getLogger().fatal("WARNING : glfwInit took {} seconds to start.", (glfwInitEnd-glfwInitBegin) / 1.0e9);
         }
 
+        // Clear the Last Exception (#7285 - Prevent Vanilla throwing an IllegalStateException due to invalid controller mappings)
+        handleLastGLFWError((error, description) -> LogManager.getLogger().error(String.format("Suppressing Last GLFW error: [0x%X]%s", error, description)));
+
         glfwDefaultWindowHints();
         glfwWindowHint(GLFW_CLIENT_API, GLFW_OPENGL_API);
         glfwWindowHint(GLFW_CONTEXT_CREATION_API, GLFW_NATIVE_CONTEXT_API);
@@ -239,12 +244,25 @@ class ClientVisualization implements EarlyProgressVisualization.Visualization {
         glVertex2f(screenWidth, 0);
         glEnd();
     }
+
     private void fbResize(long window, int width, int height) {
         if (window == this.window && width != 0 && height != 0) {
             fbSize = new int[] {width, height};
         }
     }
 
+    private void handleLastGLFWError(BiConsumer<Integer, String> handler) {
+        try (MemoryStack memorystack = MemoryStack.stackPush()) {
+            PointerBuffer pointerbuffer = memorystack.mallocPointer(1);
+            int error = GLFW.glfwGetError(pointerbuffer);
+            if (error != GLFW_NO_ERROR) {
+                long pDescription = pointerbuffer.get();
+                String description = pDescription == 0L ? "" : MemoryUtil.memUTF8(pDescription);
+                handler.accept(error, description);
+            }
+        }
+    }
+
     private void renderMessages() {
         List<Pair<Integer, StartupMessageManager.Message>> messages = StartupMessageManager.getMessages();
         for (int i = 0; i < messages.size(); i++) {