Re: [ANN] Lua 5.3.6 (rc1) now available

[Roberto Ierusalimschy <roberto@...>]

>  Roberto> I guess you are talking about this macro:
> 
>  Roberto>     #define checkstackp(L,n,p)  \
>  Roberto>       luaD_checkstackaux(L, n, \
>  Roberto>         ptrdiff_t t__ = savestack(L, p);  /* save 'p' */ \
>  Roberto>         luaC_checkGC(L),  /* stack grow uses memory */ \
>  Roberto>         p = restorestack(L, t__))  /* 'pos' part: restore 'p' */
> 
>  Roberto> What separates the macro arguments is the comma, not the
>  Roberto> semicolon. So, the call to luaC_checkGC is done before the
>  Roberto> stack reallocation.
> 
> Aha. Yes, that explains it.

We cannot put the 'pre' code inside braces because of the scope of 't__'.

I think that's what got me when I wrote the macro checkstackGC :-)

-- Roberto