C/C++ tricks

Did you know, that keeping frequently accessed field at the start of a struct/class can greatly boost access time and decrease code size? I got like 1/10 speed up.

>>17
That's not valid C. main() must have a return type of int, and using a void function where a value is expected isn't allowed.

The following code will compile, but the return value of main() is undefined:

void abc(){return 2;}
int(*func)() = abc;
int main(){return func();}