Re: [PHP-DEV] [VOTE] Abstract Syntax Tree

On Tue, Aug 19, 2014 at 11:30 AM, Laruence <[email protected]> wrote:
> Hey:
>
>   a fix could be:
> diff --git a/Zend/zend_ast.c b/Zend/zend_ast.c
> index eb35a51..f738e34 100644
> --- a/Zend/zend_ast.c
> +++ b/Zend/zend_ast.c
> @@ -33,11 +33,11 @@ static inline void *zend_ast_realloc(void *old,
> size_t old_size, size_t new_size
>   return new;
>  }
>
> -size_t zend_ast_size(zend_uint children) {
> +size_t zend_ast_size(int children) {
>   return sizeof(zend_ast) + sizeof(zend_ast *) * (children - 1);
>  }
>
> -size_t zend_ast_list_size(zend_uint children) {
> +size_t zend_ast_list_size(int children) {
>   return sizeof(zend_ast_list) + sizeof(zend_ast *) * (children - 1);
>  }
>
>
>   my compiler must take (children -1) as a unsigned

It does, the result of the expression will be.

But the fix is imo wrong. A size cannot be negative, per se.

It would be cleaner to do:

size_t zend_ast_size(int children) {
     if (children > 0) {
      return sizeof(zend_ast) + sizeof(zend_ast *) * (children - 1);
     } else {
       // 0 or sizeof(zend_ast) + sizeof(zend_ast *) if at least one
elem is allocated (NULLed).
     }
}


Cheers,
-- 
Pierre

@pierrejoye | http://www.libgd.org