Mailing lists / fpc-devel / 2018-09
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Hi,
optimize (v>=x) and (v<=y) into (v-x)<(y-x)
If the commit does what this says, it is incorrect for the case that x=v=y: (v>=x)=true, (v<=x)=true, (v-x)<(y-x) translates to (0<0) wich is false.
See https://bugs.freepascal.org/view.php?id=34292
Assuming: v=1; x=10; y=3
(v-x) < (y-x) == (1-10) < (3-10) == -9 < -7 == *true*
(v>=x) and (v<=y) == (1>=10) and (1<=3) == false and true = *false*