diff --git a/Zend/tests/gh10085_1.phpt b/Zend/tests/gh10085_1.phpt
deleted file mode 100644
index cc11c96a09d..00000000000
--- a/Zend/tests/gh10085_1.phpt
+++ /dev/null
@@ -1,22 +0,0 @@
---TEST--
-GH-10085: Assertion in add_function_array()
---FILE--
-<?php
-$i = [[], 0];
-$ref = &$i;
-$i[0] += $ref;
-var_dump($i);
-?>
---EXPECT--
-array(2) {
-  [0]=>
-  array(2) {
-    [0]=>
-    array(0) {
-    }
-    [1]=>
-    int(0)
-  }
-  [1]=>
-  int(0)
-}
diff --git a/Zend/tests/gh10085_2.phpt b/Zend/tests/gh10085_2.phpt
deleted file mode 100644
index 7895999f2cd..00000000000
--- a/Zend/tests/gh10085_2.phpt
+++ /dev/null
@@ -1,25 +0,0 @@
---TEST--
-GH-10085: Assertion in add_function_array()
---FILE--
-<?php
-$tmp = [0];
-unset($tmp[0]);
-$i = [$tmp, 0];
-unset($tmp);
-$ref = &$i;
-$i[0] += $ref;
-var_dump($i);
-?>
---EXPECT--
-array(2) {
-  [0]=>
-  array(2) {
-    [0]=>
-    array(0) {
-    }
-    [1]=>
-    int(0)
-  }
-  [1]=>
-  int(0)
-}
diff --git a/Zend/tests/gh11171.phpt b/Zend/tests/gh11171.phpt
new file mode 100644
index 00000000000..8bda7da0b7b
--- /dev/null
+++ b/Zend/tests/gh11171.phpt
@@ -0,0 +1,15 @@
+--TEST--
+GH-11171: Test
+--FILE--
+<?php
+$all = ['test'];
+foreach ($all as &$item) {
+    $all += [$item];
+}
+var_dump($all);
+?>
+--EXPECT--
+array(1) {
+  [0]=>
+  &string(4) "test"
+}
diff --git a/Zend/zend_operators.c b/Zend/zend_operators.c
index 00286cac388..d16699d698f 100644
--- a/Zend/zend_operators.c
+++ b/Zend/zend_operators.c
@@ -1039,22 +1039,16 @@ static ZEND_COLD zend_never_inline void ZEND_FASTCALL zend_binop_error(const cha
 
 static zend_never_inline void ZEND_FASTCALL add_function_array(zval *result, zval *op1, zval *op2) /* {{{ */
 {
+	if (result == op1 && Z_ARR_P(op1) == Z_ARR_P(op2)) {
+		/* $a += $a */
+		return;
+	}
 	if (result != op1) {
 		ZVAL_ARR(result, zend_array_dup(Z_ARR_P(op1)));
-		zend_hash_merge(Z_ARRVAL_P(result), Z_ARRVAL_P(op2), zval_add_ref, 0);
-	} else if (Z_ARR_P(op1) == Z_ARR_P(op2)) {
-		/* $a += $a */
 	} else {
-		/* We have to duplicate op1 (even with refcount == 1) because it may be an element of op2
-		 * and therefore its reference counter may be increased by zend_hash_merge(). That leads to
-		 * an assertion in _zend_hash_add_or_update_i() that only allows adding elements to hash
-		 * tables with RC1. See GH-10085 and Zend/tests/gh10085*.phpt */
-		zval tmp;
-		ZVAL_ARR(&tmp, zend_array_dup(Z_ARR_P(op1)));
-		zend_hash_merge(Z_ARRVAL(tmp), Z_ARRVAL_P(op2), zval_add_ref, 0);
-		zval_ptr_dtor(result);
-		ZVAL_COPY_VALUE(result, &tmp);
+		SEPARATE_ARRAY(result);
 	}
+	zend_hash_merge(Z_ARRVAL_P(result), Z_ARRVAL_P(op2), zval_add_ref, 0);
 }
 /* }}} */