Re: Bug in hook(luaV_finishOp:OP_LE)?

[Roberto Ierusalimschy <roberto@...>]

> > [...]
> > 
> > it has different result when call or not call 'lua_yield' in 'hook' fun, i
> > think there is a bug in when finish execution of an opcode(OP_LE)
> > interrupted by an yield.
> > 
> > [...]
> > ......
> > 
> > in func luaV_finishOp, i think it is necessary to invert result when both
> > R(B) and R(C) has no meta method 'TM_LE':
> > if (op == OP_LE &&  /* "<=" using "<" instead? */
> >           ttisnil(luaT_gettmbyobj(L, base + GETARG_B(inst), TM_LE)) &&
> >           ttisnil(luaT_gettmbyobj(L, base + GETARG_C(inst), TM_LE)))
> >         res = !res;  /* invert result */
> 
> Many thanks for the detailed report. We will have a look into it.

Bug indeed. You do not need C code to produce it:

t1 = setmetatable({x=1}, 
   {__le = function (a,b) coroutine.yield("yield"); return a.x <= b.x end})
t2 = {x=2}

co = coroutine.wrap(function (a,b) return a <= b end)

print(co(t2,t1))       --> yield
print(co())            --> true   (should be false)


-- Roberto