World: r3wp

REBOL doesn't have a "warning" mechanism at all, it just has an error 
mechanism. Warning mechanisms are really awkward at runtime - that 
is why you only see them in compilers or applications with runtime 
logging. And only the latter would apply to us. We have been talking 
about making a binding lint tool for R3 though, and that could easily 
generate such warnings.

(#ifndef, yes)

Is it safe to have a command without arguments return a value? Is 
there a return slot reserved anyway in the arguments frame?

the return slot is the first argument in the frame.  AFAIK the argument 
frame is always the same size no matter how many arguments to actually 
supply (0 to 8)

Ah, OK, safe then. That makes that combination a lot easier

Is there any example how to deal with objects? Especially how to 
create objects on C side.

I've found it.. I must use RL_SET_FIELD macro... but it requires 
to define all posible words.

After importing an extension, I consistently get a REBOL error if 
I allocate any non-trivial amount of memory afterwards:

>> import %./sample.so
>> array 100'000 
== REBOL System Error:
REBOL System Error #1207: assertion failed

Happens for my own extensions on both Win32 A110 and Linux A110. 
Also just tried it with Kaj's cURL extension, same problem.

Anyone else seeing this?

== REBOL System Error:
REBOL System Error #1207: assertion failed

Program terminated abnormally.
This should never happen.
Please contact www.REBOL.com with details.

Linux A110?

Yes

Thanks, I'll report it as bug.

Looks noteworthy :-)

When I go beyond 14 commands, importing segfaults. I thought people 
had made extensions with far more commands?

I don't see none of these these problems with my FMOD extension.

I'm on XP only.

Maybe you do something wrong in your extension.

Just tested your extension attached to CC (sample.c) and I cannot 
repro the assertion as well.

Thanks for testing, Oldes.

Would you mind mailing me your resulting .dll?

And what compiler did you use? GCC or MSVC?

gcc (GCC) 3.4.5 (mingw-vista special r3)

Would you mind trying the following:
http://bolka.at/2010/rebol3/tmp/sample.dll

works

Ok, so works on XP, fails on Linux and Wine. Will try Win7 later 
on.

I've tested extensively, and no matter what I do, it segfaults right 
away on init when there are more than 14 commands in the init block. 
That's indeed on Linux

Hm, a trivial extension exporting 20 commands seems to work fine 
for me:
https://gist.github.com/e9192ae7083a2fbf5d78

Both for A110 Linux and A110 Win32+Wine.

Interesting, but that's a very empty example. Can you try with command 
parameters?

I'm exporting them wrapped in a context. That may make a difference

When I split the cURL binding in two contexts, it works, so it seems 
to be some object limit

Very peculiar.

When I export a context wrapping the above 20 cmds, it still works.

export cmds: context [cmd01: command [] cmd02: ...]

Then please give them some more work to do

It also bombs out for me when the fifteenth context slot is such 
an empty command

Makes no difference even if I add 3 parameters to each of them.

Let me try with 10 parameters each.

It sure is a strange thing :-)

Most peculiar, yes.

Nope, 20 cmds with 10 params each works as well.

Maybe something to do with the length of the init block?

OK, let me upload the cURL binding source for you

I tried shortening the init block, but it didn't help

An error return code is defined for extensions, but it's not used 
anywhere in the host kit or documentation, so we don't know how to 
use it

There's also a SET_EXT_ERROR macro, but also undocumented, and it 
only allows setting an unknown number

I'm experimenting with image! as a command agrument and found this 
strange behaviour:
I have:
	img-echo: command [img [image!] ]
In RX_Call I use just:   return RXR_VALUE;

And then when I call the img-echo I get image, but with index at 
the tail so it looks like:
>> i: img-echo img
== make image! [50x20 #{
}]
>> index? i
== 1001

Is this normal? How I can set the index on the C side?

I've found solution for my answer related to warning: ../R3A110/src/include/reb-config.h:107: 
warning: ignoring #pragma warning  

To remove this warning, use this compiler option:  -Wno-unknown-pragmas