Nicolas Cellier uploaded a new version of Chronology-Core to project The Trunk:
http://source.squeak.org/trunk/Chronology-Core-nice.52.mcz

==================== Summary ====================

Name: Chronology-Core-nice.52
Author: nice
Time: 12 March 2020, 12:03:38.8371 pm
UUID: eb71ab74-c271-4a0e-bf81-ef3b0917ce67
Ancestors: Chronology-Core-mt.51

Normalize a copy of jdn,seconds,nanos so as to prevent attempts to modify a read-only literal.

=============== Diff against Chronology-Core-mt.51 ===============

Item was changed:
  ----- Method: DateAndTime>>ticks:offset: (in category 'private') -----
  ticks: ticks offset: utcOffset
  	"ticks is {julianDayNumber. secondCount. nanoSeconds}"
  
+ 	| jdn s nanos normalizedTicks |
+ 	normalizedTicks := ticks copy.
+ 	self normalize: 3 ticks: normalizedTicks base: NanosInSecond.
+ 	self normalize: 2 ticks: normalizedTicks base: SecondsInDay.
- 	| jdn s nanos |
- 	self normalize: 3 ticks: ticks base: NanosInSecond.
- 	self normalize: 2 ticks: ticks base: SecondsInDay.
  
+ 	jdn	:= normalizedTicks at: 1.
+ 	s := normalizedTicks at: 2.
+ 	nanos := normalizedTicks at: 3.
- 	jdn	:= ticks at: 1.
- 	s := ticks at: 2.
- 	nanos := ticks at: 3.
  	localOffsetSeconds := utcOffset ifNil: [0] ifNotNil: [utcOffset asSeconds].
  	utcMicroseconds := self microsecondsFromDay: jdn seconds: s nanos: nanos offset: localOffsetSeconds.
  !