Implicit declaration of function.

[ickystasis]

Sorry if this is an error on my side, I don't think it is but I'm probably not the right person to be messing with this stuff.

[D-Pyro]

double min(double a, double b) {
return a<b ? a : b;
}

[MarvinOl]

There is no need to define a function with variable casting etc...

The "standard" way of doing this is just add this line under #include lines:
#define min(X,Y) (((X) < (Y)) ? (X) : (Y))