Re: [RFA]: Fix do_cleanups if oldchain is NULL

["J. Johnston" <jjohnstn@redhat.com>]

Andrew Cagney wrote:
>> I recently solved a bug on the ia64 concerning cleanups.  What was 
>> happening was that a cleanup list was being re-initialized to NULL 
>> inside a loop and later do_cleanups() was called.  This caused the 
>> entire cleanup list to be run because the design is to run the list 
>> until the passed in cleanup is reached.  This caused other errors when 
>> the stream being used was deleted, etc...
>>
>> This patch adds a check to do_my_cleanups() so no cleanups will be 
>> performed if the passed in chain is NULL.
>>
>> Ok to commit?
> 
> 
> (hmm, no one thought to review this while I was on hols :-()
> I think the bug is in the calling code, and not utils.c.  That patch 
> unfortunatly makes a fundamental change to the core of the cleanup code 
> and there's no easy way of demonstrating that other callers aren't 
> assuming that NULL implies do all cleanups.
> 
> Andrew
> 

Perhaps, but there is no way to properly initialize a cleanup to avoid compiler 
warnings.  If you set it to NULL which is the obvious choice, this currently 
means run all cleanups.  IMHO, this is the wrong choice for the default.  I 
found no cases where NULL was passed in directly.  Do you see a case where a gdb 
routine has the right to run all previous cleanups except in an exit scenario?

-- Jeff J.

> 
>> -- Jeff J.
>>
>> 2003-12-17  Jeff Johnston  <jjohnstn@redhat.com>
>>
>>        * utils.c (do_my_cleanups): Don't do cleanups if old chain
>>        passed in is NULL.
> 
> 
> 
>