generic.inc Meaning of -11 values

[lagprogramming]

   I've been looking at generic.inc file and I've seen some "-11" ocurrences. Is it a copy/paste bug or there is a meaning for the eleven values?
   I ask because the file contains both "if (Count>4*sizeof(ptruint)-11)" and "if Count>4*sizeof(ptruint)-1 then".

For quick reference
http://svn.freepascal.org/svn/fpc/trunk/rtl/inc/generic.inc

[marcov]

My guess is 1 less than 3*sizeof(integer)=12

The 1 less because of > instead of >=