https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87310
--- Comment #3 from Róbert Kohányi <kohanyi.robert at gmail dot com> --- Created attachment 44697 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=44697&action=edit /usr/lib/gcc/x86_64-pc-msys/7.3.0/include/stdbool.h Here's the referenced <stdbool.h> on Windows using gcc 7.3.0