C callbacks getting a value of 0! Bug in D?

[Moritz Maxeiner via Digitalmars-d-learn]

On Monday, 28 August 2017 at 22:21:18 UTC, Johnson Jones wrote:
> On Monday, 28 August 2017 at 21:35:27 UTC, Steven Schveighoffer 
> wrote:
>> On 8/27/17 10:17 PM, Johnson Jones wrote:
>>> [...]
>>
>> For C/C++ interaction, always use c_... types if they are 
>> available. The idea is both that they will be correctly 
>> defined for the width, and also it will mangle correctly for 
>> C++ compilers (yes, long and int are mangled differently even 
>> when they are the same thing).
>>
>> -Steve
>
> and where are these c_ types defined? The reason I replaced 
> them was precisely because D was not finding them.

core.stdc.config

, which unfortunately doesn't appear in the online documentation 
AFAICT (something that ought to be fixed).
A common workaround is to use pattern searching tools like grep 
if you know the phrase to look for:
$ grep -Er c_long /path/to/imports
, or in this case, since these things are usually done with 
aliases:
$ grep -Er 'alias\s+\w*\s+c_long' /path/to/imports