Criteria for 1.0 (was: Re: If D becomes a failure, what's the key reason, do you think?)

[Sean Kelly]

Kirk McDonald wrote:
> Walter Bright wrote:
>> Kirk McDonald wrote:
>>
>>> Here's something that has been annoying me, and this week-old thread 
>>> is as good a place as any to bring it up: Shared library support on 
>>> Linux. I could not take D seriously if it did a "1.0" release without 
>>> this. I do hate to cram more on your plate, Walter, but I consider 
>>> this a more serious issue than even this import thing that has 
>>> gripped the newsgroup for the past week.
>>
>>
>> I know about the shared library issue on Linux. And to tell the truth, 
>> I've been procrastinating on it. The big job, -fPIC, is done. I don't 
>> know how much beyond that needs to be done.
>>
>> Will the shared libraries work with GDC?
> 
> Ha! Well, at least this simple case does:
> 
> [myso2.d]
> import std.stdio;
> 
> export extern(C)
> void mysoprint() { writefln("Hello 'so' world!"); }
> 
> [myso.d]
> export extern(C) void mysoprint();
> 
> [test.d]
> import myso;
> 
> void main() {
>     mysoprint();
> }
> 
> $ gdc -shared -Wl,-soname,libmyso.so -o libmyso.so myso2.o -lc
> /usr/bin/ld: warning: creating a DT_TEXTREL in object.
> 
> (Not sure what that means...)
> 
> $ sudo cp libmyso.so /usr/lib
> $ gdc -c test.d
> $ gdc test.o -Wl,-lmyso -o test
> $ ./test
> Hello 'so' world!
> 
> Sweet. However, I am a little concerned. When making DLLs on Windows, 
> there is some boilerplate code needed to initialize and shut down the GC 
> and do some other routine things. Is something like that needed here?

I think it is.  Perhaps the best approach would be to expose two extern 
(C) functions: one for startup and one for shutdown.  By default, these 
would be called automatically by internal/dmain2, but the user could opt 
to call them in DllInit or whatever if he knows that function will not 
be the entry point for his program.  In Ares, I'd probably call these 
"cr_init" and "cr_term" where "cr" means "compiler runtime."


Sean