Re: Potential bug in Lua when hooking functions

[Rob Kendrick <lua-l@...>]

On Mon, 20 Jul 2009 14:37:22 +0100
Jonathan Shaw <Jonathan.Shaw@microsoft.com> wrote:

> Forgive my ignorance, but how would a traditional diff be best
> displayed in a text only format?

Traditionally, using the diff tool.  For your patch, it generates the
following;

diff -aru lua-5.1.4/src/lvm.c lua-5.1.4-yeild-fix/src/lvm.c
--- lua-5.1.4/src/lvm.c	2009-03-20 18:03:04.517261443 +0000
+++ lua-5.1.4-yeild-fix/src/lvm.c	2009-07-20 14:44:18.067091491
+0100 @@ -616,11 +616,14 @@
     StkId ra;
     if ((L->hookmask & (LUA_MASKLINE | LUA_MASKCOUNT)) &&
         (--L->hookcount == 0 || L->hookmask & LUA_MASKLINE)) {
+      const lu_byte saved_status = L->status;
+      L->status = 0;
       traceexec(L, pc);
       if (L->status == LUA_YIELD) {  /* did hook yield? */
         L->savedpc = pc - 1;
         return;
       }
+      L->status = saved_status;
       base = L->base;
     }
     /* warning!! several calls may realloc the stack and invalidate `ra' */


(Incidentally, in my copy of Lua 5.1.4, this region starts around line
620, not on line 388; have you modified your copy of Lua in other ways?)

B.