On Wednesday, 9 March 2016 at 18:35:31 UTC, KlausO wrote: > So maybe they should be declared as "extern GUID ..." because > they also seem to be defined in windows\lib\uuid.lib which > comes with DMD. Declarations come from mingw and mingw doesn't have uuid.lib: https://issues.dlang.org/show_bug.cgi?id=15482