Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:76694
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: pass (pb1.pair.com: domain gmail.com designates 209.85.216.51 as permitted sender)
MIME-Version: 1.0
In-Reply-To: <CABBJUpfwOxYWeSzg-n=01c_SGATVz7Q4O0HmJNbjzrCYivwMZQ@mail.gmail.com>
References: <CAF+90c_M7nKiVLYT0vWaq8wg==Yz0ZZC1V_ke=t71rpWqKPepA@mail.gmail.com>
	<DBD5ACA0-F06A-4A14-9419-E9233A8EB178@zend.com>
	<CA+9eiLv9c4QWz19NpK5QXX-oz-HCSa-VyreCKKy6_gzBQ07xPg@mail.gmail.com>
	<CABBJUpfZe2xQncW6h_7h-WD0Tijr4RVYVkMtabXkD-wV+bZZTw@mail.gmail.com>
	<CABBJUpeaV1O5YO96gSpWaCbkvvjWozPLZMzACPj_96KP=xOCFg@mail.gmail.com>
	<CABBJUpfwOxYWeSzg-n=01c_SGATVz7Q4O0HmJNbjzrCYivwMZQ@mail.gmail.com>
Date: Tue, 19 Aug 2014 11:35:23 +0200
Message-ID: <CAEZPtU4y5GN+f_FWmz1TNnaBxJ-akJ1XsMQqVCPxBkqBPt+CfA@mail.gmail.com>
To: Laruence <laruence@php.net>
Cc: Dmitry Stogov <dmitry@zend.com>, Andi Gutmans <andi@zend.com>, Nikita Popov <nikita.ppv@gmail.com>, 
	PHP internals <internals@lists.php.net>
Content-Type: text/plain; charset=UTF-8
Subject: Re: [PHP-DEV] [VOTE] Abstract Syntax Tree
From: pierre.php@gmail.com (Pierre Joye)

On Tue, Aug 19, 2014 at 11:30 AM, Laruence <laruence@php.net> 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