From b43c87fcd064bf7df66973f0f51e655b50eaaf7e Mon Sep 17 00:00:00 2001
From: lacatoire <la.catoire@gmail.com>
Date: Fri, 16 Oct 2026 11:05:08 +0200
Subject: [PATCH] Fix the argument named by the imageaffine() element TypeError

---
 ext/gd/gd.c                                      |  2 +-
 ext/gd/tests/imageaffine_element_type_error.phpt | 15 +++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)
 create mode 100644 ext/gd/tests/imageaffine_element_type_error.phpt

diff --git a/ext/gd/gd.c b/ext/gd/gd.c
index 21fb90c3b4d1..9f6e38a2e78d 100644
--- a/ext/gd/gd.c
+++ b/ext/gd/gd.c
@@ -4142,7 +4142,7 @@ PHP_FUNCTION(imageaffine)
 					}
 					break;
 				default:
-					zend_argument_type_error(3, "contains invalid type for element %i", i);
+					zend_argument_type_error(2, "contains invalid type for element %i", i);
 					RETURN_THROWS();
 			}
 		}
diff --git a/ext/gd/tests/imageaffine_element_type_error.phpt b/ext/gd/tests/imageaffine_element_type_error.phpt
new file mode 100644
index 000000000000..e4cf2cc4336f
--- /dev/null
+++ b/ext/gd/tests/imageaffine_element_type_error.phpt
@@ -0,0 +1,15 @@
+--TEST--
+imageaffine(): the TypeError for an invalid element names the $affine argument
+--EXTENSIONS--
+gd
+--FILE--
+<?php
+$im = imagecreatetruecolor(20, 20);
+try {
+    imageaffine($im, [1, 0, null, 1, 0, 0]);
+} catch (Throwable $e) {
+    echo $e::class, ': ', $e->getMessage(), "\n";
+}
+?>
+--EXPECT--
+TypeError: imageaffine(): Argument #2 ($affine) contains invalid type for element 2