That is odd. Debugger should not be affected by what code you include...
Usual suspects:
-O- (at max -O1, but really better NO optimization) (though breakpoints often work at higher opt)
No Smart linking.
No Inlining.
Warning, if a method has the "inline" modifier, then even at -O- it will be inlined. Use {$INLINE off} at the top of the unit.