[fpc-pascal] When are used units recompiled? (more details)

[Peter Vreman]

> Apparently, there is a dependency on the System unit, and incompatibility
> between System units can cause a recompile.  Any other such dependencies?
> Is every separately compiled unit dependent on System?  If not, under
> what circumstances will it depend on System?  And on what other units?

Units and programs always depend on System. It is the main unit where all
the basic types are defined.


> That sounds rather vague.  From my analysis above, it seems that updating
> your System unit will invalidate all (?) precompiled units (at least
> the ones that somehow "depend" on it).  Or am I missing something here?

You are correct. That is the reason why it is recommended to use the
stable releases.