diff --git a/psalm-baseline.xml b/psalm-baseline.xml
index d192f9eb061..dbdec1f11d2 100644
--- a/psalm-baseline.xml
+++ b/psalm-baseline.xml
@@ -1054,6 +1054,7 @@
   <file src="src/Psalm/Internal/Analyzer/Statements/ReturnAnalyzer.php">
     <PossiblyUndefinedIntArrayOffset>
       <code><![CDATA[$method_name]]></code>
+      <code><![CDATA[$method_name]]></code>
     </PossiblyUndefinedIntArrayOffset>
     <RiskyTruthyFalsyComparison>
       <code><![CDATA[!$context->calling_function_id]]></code>
diff --git a/src/Psalm/Internal/Analyzer/Statements/ReturnAnalyzer.php b/src/Psalm/Internal/Analyzer/Statements/ReturnAnalyzer.php
index 945dfd60d1f..ec109d6b84c 100644
--- a/src/Psalm/Internal/Analyzer/Statements/ReturnAnalyzer.php
+++ b/src/Psalm/Internal/Analyzer/Statements/ReturnAnalyzer.php
@@ -277,6 +277,18 @@ public static function analyze(
                         $statements_analyzer,
                         null,
                     );
+
+                    [, $method_name] = explode('::', $cased_method_id);
+                    if ($method_name === '__construct') {
+                        IssueBuffer::maybeAdd(
+                            new InvalidReturnStatement(
+                                'No return values are expected for ' . $cased_method_id,
+                                new CodeLocation($source, $stmt->expr),
+                            ),
+                            $statements_analyzer->getSuppressedIssues(),
+                        );
+                        return;
+                    }
                 } else {
                     $declared_return_type = $storage->return_type;
                 }
diff --git a/src/Psalm/Internal/PhpVisitor/Reflector/FunctionLikeNodeScanner.php b/src/Psalm/Internal/PhpVisitor/Reflector/FunctionLikeNodeScanner.php
index b91b521ec88..bebfb1026ee 100644
--- a/src/Psalm/Internal/PhpVisitor/Reflector/FunctionLikeNodeScanner.php
+++ b/src/Psalm/Internal/PhpVisitor/Reflector/FunctionLikeNodeScanner.php
@@ -804,7 +804,9 @@ private function getTranslatedFunctionParam(
                 $this->codebase->analysis_php_version_id,
             );
 
-            if ($is_nullable) {
+            if ($param_type->isMixed()) {
+                $is_nullable = false;
+            } elseif ($is_nullable) {
                 $param_type = $param_type->getBuilder()->addType(new TNull)->freeze();
             } else {
                 $is_nullable = $param_type->isNullable();
diff --git a/tests/ArgTest.php b/tests/ArgTest.php
index 93e7f022d68..ce75f65c15c 100644
--- a/tests/ArgTest.php
+++ b/tests/ArgTest.php
@@ -357,6 +357,20 @@ function foo($a, ...$b) {}
 
                     var_caller("foo");',
             ],
+            'mixedNullable' => [
+                'code' => '<?php
+                    class A {
+                        public function __construct(public mixed $default = null) {
+                        }
+                    }
+                    $a = new A;
+                    $_v = $a->default;',
+                'assertions' => [
+                    '$_v===' => 'mixed',
+                ],
+                'ignored_issues' => [],
+                'php_version' => '8.0',
+            ],
         ];
     }
 
diff --git a/tests/ReturnTypeTest.php b/tests/ReturnTypeTest.php
index 842a79bdb37..2273bb98c7f 100644
--- a/tests/ReturnTypeTest.php
+++ b/tests/ReturnTypeTest.php
@@ -1914,6 +1914,17 @@ function foo(bool $x): never
                 'ignored_issues' => [],
                 'php_version' => '8.1',
             ],
+            'constructorsShouldReturnVoid' => [
+                'code' => <<<'PHP'
+                    <?php
+                    class A {
+                        public function __construct() {
+                            return 5;
+                        }
+                    }
+                    PHP,
+                'error_message' => 'InvalidReturnStatement',
+            ],
         ];
     }
 }