I'm trying to fix shared libraries for OSX. I've updated sections_osx.d to
support multiple images, however, the method of notifying druntime when to
load/unload images needs to be fixed.
Currently, the following method is used to register a callback for when
images are loaded, which, based on the last conversation on this topic, is
a no-go. Basically, the problem is that there is no way of unregistering
the callbacks.
https://github.com/D-Programming-Language/druntime/blob/master/src/rt/sections_osx.d#L76
So the solution is to add __attribute__((constructor/destructor)) calls to
all D binaries on OSX to initialize the images.
The code looks like this:
http://dpaste.com/0SF46B6
So my question is, what is the best way to get this code into the binary?
I suppose the code could be pre-compiled into an object file and linked by
dmd during compilation, but adding external dependencies to dmd seems like
a bad idea.
I would say DMD could generate this code, but where would it go?
I don't think it would be right to add the __constructors__ to a random
*.o produced by the compiler, because people will expect *.o files to
behave like *.o files. On the other hand, if the __constructors__ were to
be added by dmd at link-time, and someone used a linker other than dmd, it
would not add in the __constructor__ code, and thus generate a defective
dylib. This is a complicated problem with many things to consider, so I'm
not exactly sure where to go from here.
Any ideas on this would be much appreciated.
Thanks,
Bit
