*: add optimization barrier to all "G trick" locations

diff --git a/editors/vi.c b/editors/vi.c
index 6f4bd06..d2d2670 100644
--- a/editors/vi.c
+++ b/editors/vi.c
@@ -233,7 +233,7 @@
 #define readbuffer     (G.readbuffer    )
 #define scr_out_buf    (G.scr_out_buf   )
 #define INIT_G() do { \
-	PTR_TO_GLOBALS = xzalloc(sizeof(G)); \
+	SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
 } while (0)
 
 static int init_text_buffer(char *); // init from file or create new