Add ImportC compiler to dmd

[Max Haughton]

On Monday, 10 May 2021 at 02:00:26 UTC, Brian wrote:
> On Monday, 10 May 2021 at 01:53:26 UTC, Walter Bright wrote:
>> On 5/9/2021 6:13 PM, Max Haughton wrote:
>>> ```
>>> #include <stdio.h>
>>> inline int square(int num) {
>>>      return num * num;
>>> }
>>> 
>>> int main()
>>> {
>>>      printf("%d\n", square(3));
>>> }
>>> ```
>>> fails to link in C but not in C++.
>>
>> I just tried it with gcc, it links. It does not with clang. 
>> Examination of clang's output shows it treated it as extern. I 
>> don't really understand what's going on with clang here, but 
>> that code will work with DMD.
>
> It links on clang 11.0.1 here at -O2 or higher (including -Os 
> and -Oz).
> Also links with pcc -O and even tcc!

See my previous comment and think about what inlining does to the 
assembly.