From 7484a7fd95b7547ee649ce77b974ae75694c963d Mon Sep 17 00:00:00 2001
From: Joseph Burton <burtonjae@hotmail.co.uk>
Date: Tue, 30 Sep 2025 13:38:13 +0100
Subject: [PATCH] Call visitAnnotableParameterCount (#1376)

---
 .../minecraft/AnnotationsApplyVisitor.java    | 27 +++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/src/main/java/net/fabricmc/loom/configuration/providers/minecraft/AnnotationsApplyVisitor.java b/src/main/java/net/fabricmc/loom/configuration/providers/minecraft/AnnotationsApplyVisitor.java
index 96a37748..786b6114 100644
--- a/src/main/java/net/fabricmc/loom/configuration/providers/minecraft/AnnotationsApplyVisitor.java
+++ b/src/main/java/net/fabricmc/loom/configuration/providers/minecraft/AnnotationsApplyVisitor.java
@@ -28,6 +28,7 @@ import org.objectweb.asm.AnnotationVisitor;
 import org.objectweb.asm.ClassVisitor;
 import org.objectweb.asm.FieldVisitor;
 import org.objectweb.asm.MethodVisitor;
+import org.objectweb.asm.Opcodes;
 import org.objectweb.asm.RecordComponentVisitor;
 import org.objectweb.asm.Type;
 import org.objectweb.asm.TypePath;
@@ -240,8 +241,19 @@ public record AnnotationsApplyVisitor(AnnotationsData annotationsData) implement
 			}
 
 			return new MethodVisitor(Constants.ASM_VERSION, mv) {
+				int syntheticParameterCount = 0;
+				boolean visitedAnnotableParameterCount = false;
 				boolean hasAddedAnnotations = false;
 
+				@Override
+				public void visitParameter(String name, int access) {
+					if ((access & Opcodes.ACC_SYNTHETIC) != 0) {
+						syntheticParameterCount++;
+					}
+
+					super.visitParameter(name, access);
+				}
+
 				@Override
 				public AnnotationVisitor visitAnnotation(String descriptor, boolean visible) {
 					if (methodData.annotationsToRemove().contains(Type.getType(descriptor).getInternalName())) {
@@ -271,6 +283,16 @@ public record AnnotationsApplyVisitor(AnnotationsData annotationsData) implement
 					return super.visitParameterAnnotation(parameter, descriptor, visible);
 				}
 
+				@Override
+				public void visitAnnotableParameterCount(int parameterCount, boolean visible) {
+					if (!visible && !methodData.parameters().isEmpty()) {
+						parameterCount = Math.max(parameterCount, Type.getArgumentCount(descriptor) - syntheticParameterCount);
+						visitedAnnotableParameterCount = true;
+					}
+
+					super.visitAnnotableParameterCount(parameterCount, visible);
+				}
+
 				@Override
 				public void visitCode() {
 					addMethodAnnotations();
@@ -306,6 +328,11 @@ public record AnnotationsApplyVisitor(AnnotationsData annotationsData) implement
 						}
 					}
 
+					if (!visitedAnnotableParameterCount && !methodData.parameters().isEmpty()) {
+						mv.visitAnnotableParameterCount(Type.getArgumentCount(descriptor) - syntheticParameterCount, false);
+						visitedAnnotableParameterCount = true;
+					}
+
 					methodData.parameters().forEach((paramIndex, paramData) -> {
 						for (AnnotationNode annotation : paramData.annotationsToAdd()) {
 							AnnotationVisitor av = mv.visitParameterAnnotation(paramIndex, annotation.desc, false);