diff --git a/vlib/gg/gg.v b/vlib/gg/gg.v
index f5b4f7fa4a..d37cb0d624 100644
--- a/vlib/gg/gg.v
+++ b/vlib/gg/gg.v
@@ -297,7 +297,7 @@ fn gg_cleanup_fn(user_data voidptr) {
 	}
 }
 
-fn gg_fail_fn(msg charptr, user_data voidptr) {
+fn gg_fail_fn(msg &char, user_data voidptr) {
 	mut g := unsafe { &Context(user_data) }
 	vmsg := unsafe { tos3(msg) }
 	if g.config.fail_fn != voidptr(0) {
diff --git a/vlib/sokol/sapp/sapp_structs.v b/vlib/sokol/sapp/sapp_structs.v
index 649fc4caff..594f1c5873 100644
--- a/vlib/sokol/sapp/sapp_structs.v
+++ b/vlib/sokol/sapp/sapp_structs.v
@@ -6,31 +6,31 @@ pub:
 	frame_cb                      fn ()
 	cleanup_cb                    fn ()
 	event_cb                      fn (&C.sapp_event) //&sapp_event)
-	fail_cb                       fn (byteptr)
+	fail_cb                       fn (&byte)
 	user_data                     voidptr // these are the user-provided callbacks with user data
 	init_userdata_cb              fn (voidptr)
 	frame_userdata_cb             fn (voidptr)
 	cleanup_userdata_cb           fn (voidptr)
 	event_userdata_cb             fn (&C.sapp_event, voidptr)
-	fail_userdata_cb              fn (byteptr, voidptr)
-	width                         int     // the preferred width of the window / canvas
-	height                        int     // the preferred height of the window / canvas
-	sample_count                  int     // MSAA sample count
-	swap_interval                 int     // the preferred swap interval (ignored on some platforms)
-	high_dpi                      bool    // whether the rendering canvas is full-resolution on HighDPI displays
-	fullscreen                    bool    // whether the window should be created in fullscreen mode
-	alpha                         bool    // whether the framebuffer should have an alpha channel (ignored on some platforms)
-	window_title                  byteptr // the window title as UTF-8 encoded string
-	user_cursor                   bool    // if true, user is expected to manage cursor image in SAPP_EVENTTYPE_UPDATE_CURSOR
-	enable_clipboard              bool    // enable clipboard access, default is false
-	clipboard_size                int     // max size of clipboard content in bytes
-	html5_canvas_name             byteptr // the name (id) of the HTML5 canvas element, default is "canvas"
-	html5_canvas_resize           bool    // if true, the HTML5 canvas size is set to sapp_desc.width/height, otherwise canvas size is tracked
-	html5_preserve_drawing_buffer bool    // HTML5 only: whether to preserve default framebuffer content between frames
-	html5_premultiplied_alpha     bool    // HTML5 only: whether the rendered pixels use premultiplied alpha convention
-	html5_ask_leave_site          bool    // initial state of the internal html5_ask_leave_site flag (see sapp_html5_ask_leave_site())
-	ios_keyboard_resizes_canvas   bool    // if true, showing the iOS keyboard shrinks the canvas
-	gl_force_gles2                bool    // if true, setup GLES2/WebGL even if GLES3/WebGL2 is available
+	fail_userdata_cb              fn (&char, voidptr)
+	width                         int   // the preferred width of the window / canvas
+	height                        int   // the preferred height of the window / canvas
+	sample_count                  int   // MSAA sample count
+	swap_interval                 int   // the preferred swap interval (ignored on some platforms)
+	high_dpi                      bool  // whether the rendering canvas is full-resolution on HighDPI displays
+	fullscreen                    bool  // whether the window should be created in fullscreen mode
+	alpha                         bool  // whether the framebuffer should have an alpha channel (ignored on some platforms)
+	window_title                  &byte // the window title as UTF-8 encoded string
+	user_cursor                   bool  // if true, user is expected to manage cursor image in SAPP_EVENTTYPE_UPDATE_CURSOR
+	enable_clipboard              bool  // enable clipboard access, default is false
+	clipboard_size                int   // max size of clipboard content in bytes
+	html5_canvas_name             &byte // the name (id) of the HTML5 canvas element, default is "canvas"
+	html5_canvas_resize           bool  // if true, the HTML5 canvas size is set to sapp_desc.width/height, otherwise canvas size is tracked
+	html5_preserve_drawing_buffer bool  // HTML5 only: whether to preserve default framebuffer content between frames
+	html5_premultiplied_alpha     bool  // HTML5 only: whether the rendered pixels use premultiplied alpha convention
+	html5_ask_leave_site          bool  // initial state of the internal html5_ask_leave_site flag (see sapp_html5_ask_leave_site())
+	ios_keyboard_resizes_canvas   bool  // if true, showing the iOS keyboard shrinks the canvas
+	gl_force_gles2                bool  // if true, setup GLES2/WebGL even if GLES3/WebGL2 is available
 	native_render                 bool
 }