Nicolas Cellier uploaded a new version of Kernel to project The Trunk:
http://source.squeak.org/trunk/Kernel-nice.1041.mcz

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

Name: Kernel-nice.1041
Author: nice
Time: 21 September 2016, 9:06:09.983013 pm
UUID: 80f9f68f-fad8-42d7-b1bc-bfa1ee876629
Ancestors: Kernel-nice.1040

The last bits of intSpec are zero, so no need to mask it.
Those bits are used in instances only - see intSpec comment.

=============== Diff against Kernel-nice.1040 ===============

Item was changed:
  ----- Method: Behavior>>isHalfWords (in category 'testing') -----
  isHalfWords
  	"Answer true if the receiver is made of 16-bit instance variables."
  
+ 	^self instSpec = 2r1100!
- 	^(self instSpec bitAnd: 2r11100) = 2r1100!

Item was changed:
  ----- Method: Behavior>>isWords (in category 'testing') -----
  isWords
  	"Answer true if the receiver is made of 32-bit instance variables."
  
+ 	^self instSpec = 2r1010!
- 	^(self instSpec bitAnd: 2r11110) = 2r1010!