Hi Dave, hi Nicolas --
I am working in Windows 10.
I cannot reproduce on Linux 64 bit either: (Character value: 16r8000) asInteger hex ==> '16r8000'
That's not how you would reproduce it. The bug affects character literals, not character objects/instances. You have to evaluate code on that character literal.
Maybe this picture helps:
Best, Marcel Am 08.03.2022 18:56:09 schrieb David T. Lewis lewis@mail.msen.com:
I cannot reproduce on Linux 64 bit either:
(Character value: 16r8000) asInteger hex ==> '16r8000'
Dave
On Tue, Mar 08, 2022 at 06:45:23PM +0100, Nicolas Cellier wrote:
Hi Marcel, which OS ? I cannot reproduce on macos 64,
Cog[Spur] VM [CoInterpreterPrimitives VMMaker.oscog-eem.3172] 5.20211023.2003 Mac OS X built on Mar 6 2022 15:31:16 CET Compiler: 4.2.1 Compatible Apple LLVM 10.0.1 (clang-1001.0.46.4) platform sources revision VM: 202110232003
Le mar. 8 mars 2022 ?? 17:57, Marcel Taeumel a ??crit :
Hi Eliot, hi all --
I think we have an sign-bit bug for character literals with code points > 16r7FFF.
Steps to reproduce:
- Print it: "Character value: 16r8000"
- Inspect the result by evaluating the character literal or send
#asInteger to it. It will most likely not render in a standard Squeak and show up like "$? asInteger".
In a 32-bit VM, I will get the (positive) integer value 16r3FFF8000. In a 64-bit VM, I will get the (negative) integer value '-16r8000'.
Somehow, starting at bit 0, the bits 16 to 29 flip from 0 to 1. In 64-bit, this means a negative number. Not sure about bits 30 and 31 here.
Is there a bug in the upper tag bits of immediate characters? Is this related to the 2-byte or 3-byte byte codes in SistaV1?
Works fine up to 16r7FFF. (This is unrelated to #leadingChar. Mine was 0 in this experiment.)
VM: 202112201228 (VMMaker.oscog-eem.3116)
Best, Marcel