diff --git a/src/FFI.php b/src/FFI.php
index 194db6f..72c91a2 100644
--- a/src/FFI.php
+++ b/src/FFI.php
@@ -163,9 +163,9 @@ public static function version(): string
      */
     public static function atLeast(int $x, int $y, int $z = 0): bool
     {
-        return self::$library_major > $x ||
-            self::$library_major == $x && self::$library_minor > $y ||
-            self::$library_major == $x && self::$library_minor == $y && self::$library_micro >= $z;
+        return self::$library_major > $x
+            || (self::$library_major === $x && self::$library_minor > $y)
+            || (self::$library_major === $x && self::$library_minor === $y && self::$library_micro >= $z);
     }
 
     /**
diff --git a/src/GObject.php b/src/GObject.php
index 964393a..a092e83 100644
--- a/src/GObject.php
+++ b/src/GObject.php
@@ -152,7 +152,7 @@ private static function getMarshaler(string $name, callable $callback): ?Closure
                         ?CData $data
                     ) use (&$callback): void {
                         assert($numberOfParams === 3);
-                        /*
+                        /**
                          * Signature: gint64(VipsSourceCustom* source, void* buffer, gint64 length, void* handle)
                          */
                         $bufferLength = (int)FFI::gobject()->g_value_get_int64(\FFI::addr($params[2]));
@@ -180,7 +180,7 @@ private static function getMarshaler(string $name, callable $callback): ?Closure
                         ?CData $data
                     ) use (&$callback): void {
                         assert($numberOfParams === 3);
-                        /*
+                        /**
                          * Signature: gint64(VipsSourceCustom* source, gint64 offset, int whence, void* handle)
                          */
                         $offset = (int)FFI::gobject()->g_value_get_int64(\FFI::addr($params[1]));
@@ -201,7 +201,7 @@ private static function getMarshaler(string $name, callable $callback): ?Closure
                         ?CData $data
                     ) use (&$callback): void {
                         assert($numberOfParams === 3);
-                        /*
+                        /**
                          * Signature: gint64(VipsTargetCustom* target, void* buffer, gint64 length, void* handle)
                          */
                         $bufferPointer = FFI::gobject()->g_value_get_pointer(\FFI::addr($params[1]));
@@ -223,7 +223,7 @@ private static function getMarshaler(string $name, callable $callback): ?Closure
                         CData  $hint,
                         ?CData $data
                     ) use (&$callback): void {
-                        assert($numberOfParams === 0);
+                        assert($numberOfParams === 1);
                         /**
                          * Signature: void(VipsTargetCustom* target, void* handle)
                          */