diff --git a/src/PhpDoc/TypeNodeResolver.php b/src/PhpDoc/TypeNodeResolver.php
index 8af74bf926..065f8ade8a 100644
--- a/src/PhpDoc/TypeNodeResolver.php
+++ b/src/PhpDoc/TypeNodeResolver.php
@@ -592,6 +592,8 @@ private function resolveUnionTypeNode(UnionTypeNode $typeNode, NameScope $nameSc
 			$arrayTypeType = TypeCombinator::union(...$arrayTypeTypes);
 			$addArray = true;
 
+			// Pass 1: merge non-array iterables (ObjectType, IterableType)
+			$nonArrayMerged = false;
 			foreach ($otherTypeTypes as &$type) {
 				if (!$type->isIterable()->yes() || !$type->getIterableValueType()->isSuperTypeOf($arrayTypeType)->yes()) {
 					continue;
@@ -599,18 +601,34 @@ private function resolveUnionTypeNode(UnionTypeNode $typeNode, NameScope $nameSc
 
 				if ($type instanceof ObjectType && !$type instanceof GenericObjectType) {
 					$type = new IntersectionType([$type, new IterableType(new MixedType(), $arrayTypeType)]);
-				} elseif ($type instanceof ArrayType) {
-					$type = new ArrayType(new MixedType(), $arrayTypeType);
-				} elseif ($type instanceof ConstantArrayType) {
-					$type = new ArrayType(new MixedType(), $arrayTypeType);
+					$nonArrayMerged = true;
 				} elseif ($type instanceof IterableType) {
 					$type = new IterableType(new MixedType(), $arrayTypeType);
+					$nonArrayMerged = true;
 				} else {
 					continue;
 				}
 
 				$addArray = false;
 			}
+			unset($type);
+
+			// Pass 2: merge array types only if non-array iterables were also merged
+			if ($nonArrayMerged) {
+				foreach ($otherTypeTypes as &$type) {
+					if (!$type->isIterable()->yes() || !$type->getIterableValueType()->isSuperTypeOf($arrayTypeType)->yes()) {
+						continue;
+					}
+
+					if (!($type instanceof ArrayType) && !($type instanceof ConstantArrayType)) {
+						continue;
+					}
+
+					$type = new ArrayType(new MixedType(), $arrayTypeType);
+					$addArray = false;
+				}
+				unset($type);
+			}
 
 			if ($addArray) {
 				$otherTypeTypes[] = new ArrayType(new MixedType(), $arrayTypeType);
diff --git a/tests/PHPStan/Rules/Functions/MissingFunctionParameterTypehintRuleTest.php b/tests/PHPStan/Rules/Functions/MissingFunctionParameterTypehintRuleTest.php
index 7d43d80c8d..c72961b38b 100644
--- a/tests/PHPStan/Rules/Functions/MissingFunctionParameterTypehintRuleTest.php
+++ b/tests/PHPStan/Rules/Functions/MissingFunctionParameterTypehintRuleTest.php
@@ -33,6 +33,11 @@ public function testRule(): void
 				'Function MissingFunctionParameterTypehint\namespacedFunction() has parameter $d with no type specified.',
 				24,
 			],
+			[
+				'Function MissingFunctionParameterTypehint\intIterableTypehint() has parameter $a with no value type specified in iterable type array.',
+				31,
+				MissingTypehintCheck::MISSING_ITERABLE_VALUE_TYPE_TIP,
+			],
 			[
 				'Function MissingFunctionParameterTypehint\missingArrayTypehint() has parameter $a with no value type specified in iterable type array.',
 				36,
diff --git a/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php b/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php
index 99480a4061..43ced7b2cb 100644
--- a/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php
+++ b/tests/PHPStan/Rules/Methods/CallMethodsRuleTest.php
@@ -3938,4 +3938,13 @@ public function testBug11463(): void
 		]);
 	}
 
+	public function testBug3128(): void
+	{
+		$this->checkThisOnly = false;
+		$this->checkNullables = true;
+		$this->checkUnionTypes = true;
+		$this->checkExplicitMixed = false;
+		$this->analyse([__DIR__ . '/data/bug-3128.php'], []);
+	}
+
 }
diff --git a/tests/PHPStan/Rules/Methods/data/bug-3128.php b/tests/PHPStan/Rules/Methods/data/bug-3128.php
new file mode 100644
index 0000000000..f1b7e4c2a5
--- /dev/null
+++ b/tests/PHPStan/Rules/Methods/data/bug-3128.php
@@ -0,0 +1,24 @@
+<?php declare(strict_types = 1);
+
+namespace Bug3128;
+
+use stdClass;
+
+final class HelloWorld
+{
+	/**
+	 * @param array|stdClass[] $foo
+	 */
+	public function addTos($foo): void {
+	}
+
+	/**
+	 * @param stdClass[]|array $bar
+	 */
+	public function addTosReversed($bar): void {
+	}
+}
+
+$a = new HelloWorld();
+$a->addTos([1]);
+$a->addTosReversed([1]);