Idea #1 on integrating RC with GC

[Paulo Pinto]

On Thursday, 6 February 2014 at 08:38:57 UTC, Ola Fosheim Grøstad 
wrote:
> On Thursday, 6 February 2014 at 08:06:54 UTC, Paulo Pinto wrote:
>> That won't play ball with third party libraries distributed in 
>> binary form.
>
> That is not obvious, you specify the runtime. Anyway, whole 
> program analysis also does not play well with binary libraries 
> without detailed semantic metadata.

So what do you do when different libraries require different 
runtimes?

To be more specific to my previous comment. Objective-C GC 
required special compilation flags and care needed to be taken in 
GC enabled code, like in C GCs.

This did not played well when mixing code that used the GC 
enabled runtime, with code that did not.

Thus the endless causes of core dumps in Objective-C code that 
made use of the GC.

The Apple decision to create ARC and dump the GC wasn't because 
it is better as they later sold it, but because the compiler 
inserts for the developer the usual [... retain]/[... release] 
calls that they were already writing since the NeXT days.

So no distinct runtimes were required as the generated code is no 
different than an Objective-C developer would have written by 
hand.

This was the best way to achieve some form of automatic memory 
management, while preserving compatibility across libraries 
delivered in binary form.

>
> Does shared_ptr in C++11 work with binary libraries that use 
> it, if the it is compiled with a compiler from another vendor?

As far as I am aware, no.

In any case there isn't a standard C++ ABI defined. Well, there 
are a few, but vendors don't use them.