diff --git a/src/Psalm/Checker/ClassLikeChecker.php b/src/Psalm/Checker/ClassLikeChecker.php
index 31121a7f6..b407c5aea 100644
--- a/src/Psalm/Checker/ClassLikeChecker.php
+++ b/src/Psalm/Checker/ClassLikeChecker.php
@@ -1067,11 +1067,13 @@ abstract class ClassLikeChecker extends SourceChecker implements StatementsSourc
      *
      * @param  string       $fq_class_name
      * @param  FileChecker  $file_checker
+     * @param  CodeLocation $code_location
      * @return bool
      */
     public static function classOrInterfaceExists(
         $fq_class_name,
-        FileChecker $file_checker
+        FileChecker $file_checker,
+        CodeLocation $code_location = null
     ) {
         if (!ClassChecker::classExists($fq_class_name, $file_checker) &&
             !InterfaceChecker::interfaceExists($fq_class_name, $file_checker)
@@ -1079,7 +1081,7 @@ abstract class ClassLikeChecker extends SourceChecker implements StatementsSourc
             return false;
         }
 
-        if ($file_checker->project_checker->collect_references) {
+        if ($file_checker->project_checker->collect_references && $code_location) {
             $class_storage = ClassLikeChecker::$storage[strtolower($fq_class_name)];
             $class_storage->referencing_locations[] = $code_location;
         }
diff --git a/src/Psalm/Checker/Statements/Expression/CallChecker.php b/src/Psalm/Checker/Statements/Expression/CallChecker.php
index e91e84099..975c4d9cf 100644
--- a/src/Psalm/Checker/Statements/Expression/CallChecker.php
+++ b/src/Psalm/Checker/Statements/Expression/CallChecker.php
@@ -1434,14 +1434,18 @@ class CallChecker
                                 $offset_value_type = Type::parseString($arg->value->value);
                             }
 
-                            // register class if the class exists
-                            if ($offset_value_type instanceof TNamedObject) {
-                                ClassLikeChecker::checkFullyQualifiedClassLikeName(
-                                    $offset_value_type->value,
-                                    $statements_checker->getFileChecker(),
-                                    new CodeLocation($statements_checker->getSource(), $arg->value),
-                                    $statements_checker->getSuppressedIssues()
-                                );
+                            if ($offset_value_type) {
+                                foreach ($offset_value_type->types as $offset_value_type_part) {
+                                    // register class if the class exists
+                                    if ($offset_value_type_part instanceof TNamedObject) {
+                                        ClassLikeChecker::checkFullyQualifiedClassLikeName(
+                                            $offset_value_type_part->value,
+                                            $statements_checker->getFileChecker(),
+                                            new CodeLocation($statements_checker->getSource(), $arg->value),
+                                            $statements_checker->getSuppressedIssues()
+                                        );
+                                    }
+                                }
                             }
 
                             if ($generic_params === null) {