Thread 1: breakpoint 1.1 2.1 (1)

i am using Xcode to code some cpp functions, but these days I found a weird error occurring in my codes: when it comes to error, the main function concludes:

int orderedC[11] = {3, 4, 7, 10, 15, 19, 25, 30, 41, 50, 70}; BiLink<int> BC(orderedC,11); //BiTreeLink class BC.function1(); return 0;

i don't know why even when function1() is totally blank like : void function1(){ //nothing here!!!! };

sometime i just cut the function1 codes and just paste it , the error (Thread 1: breakpoint 1.1 2.1 (1) )is fixed.