Re: [Tinycc-devel] VLAs broken on mob branch

[Sergey Korshunoff]

Hi!
> It looks that
> +        vla_sp_save();
> is enough to fix a problem

I don't understand a problem but
another version of the patch is:

--- tinycc.orig/tccgen.c        2015-04-25 06:55:48.000000000 +0300
+++ tinycc/tccgen.c     2015-04-25 10:11:07.000000000 +0300
@@ -5450,7 +5450,7 @@
         int a;

         /* save current stack pointer */
-        if (vla_flags & VLA_NEED_NEW_FRAME) {
+        if (vla_flags & (VLA_NEED_NEW_FRAME | VLA_IN_SCOPE)) {
             vla_sp_save();
             vla_flags = VLA_IN_SCOPE;
             vla_sp_loc = &vla_sp_loc_tmp;

I also try the following:
static void vla_sp_save(void) {
    if (!(vla_flags & VLA_SP_LOC_SET)) {
        *vla_sp_loc = (loc -= PTR_SIZE);
        vla_flags |= VLA_SP_LOC_SET;
    }
//    if (!(vla_flags & VLA_SP_SAVED)) {
        gen_vla_sp_save(*vla_sp_loc);
//        vla_flags |= VLA_SP_SAVED;
//    }
}

Why vla_sp_save() is protected by VLA_SP_SAVED ? How it works with a
multiple VLA's ?