ImportC and #include files

[Walter Bright]

On 4/29/2023 2:00 PM, bachmeier wrote:
> On Thursday, 27 April 2023 at 20:16:32 UTC, Walter Bright wrote:
> 
>> Thanks! Every .h file we can make work makes ImportC that much more useful. 
>> It's a high leverage activity for time invested.
> 
> I filed one earlier today:
> 
> https://issues.dlang.org/show_bug.cgi?id=23867
> 
> Seems to have an easy fix. I added
> 
> #define __builtin_isnan isnan
> 
> to the .c file and it compiled.

Do a PR to add this to importc.h and take the credit for the fix!