Calling D from C

[Steven Schveighoffer]

On Mon, 12 Mar 2012 11:17:31 -0400, Alex Rønne Petersen  
<xtzgzorex at gmail.com> wrote:

> On 12-03-2012 16:09, Chris W. wrote:
>> On Monday, 12 March 2012 at 15:00:31 UTC, Steven Schveighoffer wrote:
>>> On Mon, 12 Mar 2012 10:53:09 -0400, Chris W. <wendlec at cd.ie> wrote:
>>>
>>>> I have a problem when calling D functions from C. While I can
>>>> perform simple arithmetic operations (i.e. the calculation is
>>>> performed in D and returned to C), I experience problems when
>>>> trying to perform string/char operations or call functions from
>>>> the D standard library (e.g. writefln()). The usual error message
>>>> I get is either "Bus error" or "Segmentation fault". I haven't
>>>> been able to find the reason for this. The programs compile and
>>>> link, however, when run, they terminate with "Bus error" whenever
>>>> a D function is performed within the D code, e.g. something like
>>>> char[] s2 = s.dup; (s is a char* passed from C). Any hint or help
>>>> would be appreciated.
>>>>
>>>> I am using Mac OS X, 10.6.7
>>>
>>> If C is running your application startup, you must initialize D's
>>> runtime from your C main routine.
>>>
>>> -Steve
>>
>> Yes, I am using extern (C) and in my C main function I call
>>
>> gc_init();
>> thread_attachThis();
>>
>> This works fine for primitive types such as int + int calculations. But
>> anything more sophisticated renders a Bus error. I am sure it is just
>> some little detail I have forgotten.
>
> Don't forget to call this:  
> https://github.com/D-Programming-Language/druntime/blob/master/src/core/runtime.d#L33
>
> Documented here:  
> https://github.com/D-Programming-Language/druntime/blob/master/src/core/runtime.d#L101

More appropriate:

http://dlang.org/phobos/core_runtime.html#initialize

And actually, I think this should do everything necessary.  No need to  
call gc_init and thread_attachThis().

-Steve