Regression test

tests/PHPStan/Analyser/NodeScopeResolverTest.php

@@ -679,6 +679,10 @@ public function dataFileAsserts(): iterable
 			yield from $this->gatherAssertTypes(__DIR__ . '/data/hash-functions-74.php');
 		}
 
+		if (PHP_VERSION_ID >= 80000) {
+			yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-6308.php');
+		}
+
 		yield from $this->gatherAssertTypes(__DIR__ . '/data/bug-6500.php');
 	}
 

tests/PHPStan/Analyser/data/bug-6308.php

@@ -0,0 +1,31 @@
+<?php // lint >= 8.0
+
+declare(strict_types=1);
+
+namespace Bug6308;
+
+use function PHPStan\Testing\assertType;
+
+class BaseFinderStatic
+{
+	static public function find(): false|static
+	{
+		return false;
+	}
+}
+
+final class UnionStaticStrict extends BaseFinderStatic
+{
+	public function something()
+	{
+		assertType('Bug6308\UnionStaticStrict|false', $this->find());
+	}
+}
+
+class UnionStaticStrict2 extends BaseFinderStatic
+{
+	public function something()
+	{
+		assertType('static(Bug6308\UnionStaticStrict2)|false', $this->find());
+	}
+}