_sbrk is pulled in when system
malloc is used. It is fine to use
new (anywhere in code called by the Patch constructor), but for
free we have macros defined to avoid the libc implementations.
Probably what you need to do is add an include:
#include "basicmaths.h" to
.cpp files (the latter can instead
If it is not
malloc, then there could be some other libc call that uses it e.g.
printf() (don't use printf!)