https://bugs.winehq.org/show_bug.cgi?id=46098
--- Comment #6 from Zebediah Figura z.figura12@gmail.com --- (In reply to Georg Sauthoff from comment #5)
I cross-compiled this with mingw (using the Fedora packages), i.e.:
$ x86_64-w64-mingw32-gcc -Wall test_ftruncate.cc -o test_ftruncate.exe
Ah, okay, I see mingw aliases that to _chsize().