Re: How do I patch my binary

[Stan Shebs <stan@codesourcery.com>]

On 11/25/10 6:42 AM, Jonas Maebe wrote:
>
> On 25 Nov 2010, at 15:16, Marc Khouzam wrote:
>
>> Here is the XCode doc about Fix and Continue which explains it nicely 
>> for a user:
>> http://developer.apple.com/library/mac/#documentation/DeveloperTools/Conceptual/XcodeDebugging/230-Modifying_Running_Code/modifying_running_code.html 
>>
>
> Note that in the mean time that functionality has been deprecated by 
> Apple, and may even have already been completely removed from the 
> latest Xcode releases. It also never worked that well (hence the 
> deprecation, I guess).

One of the critical aspects to making it work was that all references 
were dynamic and indirected, so that everything could end up in 
different locations after the fix and yet still be found when you 
resumed execution.  But that meant special compiler flags, and more 
differences between "development" and "production" code. (I note the 
contemporaneous discussion about compiler options for Linux.)

In the generic Linux/ELF/ABI etc context, I think it's going to be even 
harder to make it work reliably enough for users to trust.  Certainly it 
was disappointing at Apple, to have put forth the coordinated effort and 
then not seen much uptake.

Stan