On Sat, Jan 16, 2010 at 08:16:06AM +0530, K. K. Subramaniam wrote:
On Friday 15 January 2010 10:46:45 pm Bert Freudenberg wrote:
On 15.01.2010, at 16:58, K. K. Subramaniam wrote:
Scratch 1.4 (Linux) of 30-Nov-2009 on 3.11-3 VM. Break into Scratch and do "Socket initializeNetwork".
So it does not occur in normal operation?
Only if you define "normal" as "offline" ;-). Any operation which uses networking (url block) goes through this method and it will fail when run under the 3.11.3 VM built from unix-3.11.3-vmm or svn trunk.
BTW, Scratch image is just an example which has numbered primitives.
The 3.10-4 VM has primitiveObsoleteIndexedPrimitive in slot 207 in platforms/unix/src/vm/interp.c while the 3.11.3 tar.gz and the trunk contain primitiveFail. The change crept in r1935 through vmm-dtl-126.
Is this intentional or an oversight?
Sorry I was not able to reply earlier. The change was intentional, but the effect on Scratch was not.
Some of the obsolete primitives had to be dropped when we added the block closure support. This happened in February 2009 (VMMaker-eem.114 in the SqS/VMMaker). Specifically, we changed from this, which redirects the numbered primitives:
"Networking Primitives (200-225) - NO LONGER INDEXED" (200 225 primitiveObsoleteIndexedPrimitive)
to this, which reallocates the numbers for closure support and for future COG integration:
"new closure primitives (were Networking primitives)" (200 primitiveClosureCopyWithCopiedValues) (201 primitiveClosureValue) "value" (202 primitiveClosureValue) "value:" (203 primitiveClosureValue) "value:value:" (204 primitiveClosureValue) "value:value:value:" (205 primitiveClosureValue) "value:value:value:value:" (206 primitiveClosureValueWithArgs) "valueWithArguments:"
(207 209 primitiveFail) "reserved for Cog primitives"
The obsolete primitive redirection had been in place for at least five years, so backward compatibility had been preserved for some time.
Question for Subbu: Is this an important issue may affect a large number of Scratch users? In other words, are there kids trying to run Scratch, and their Scratch image stops working properly after Squeak gets updated to use a new VM?
And a thought for the vm-dev list: I don't know if there might be a technical solution to this, but it might be possible to use a strategy in which the some of the old primitive lookups are preserved (at least for the range 207 through 225) if and only if the image format is pre-closures. Follow ups to this on vm-only.
Dave
"David" == David T Lewis lewis@mail.msen.com writes:
David> Question for Subbu: Is this an important issue may affect a large number David> of Scratch users? In other words, are there kids trying to run Scratch, David> and their Scratch image stops working properly after Squeak gets updated David> to use a new VM?
As I recall, one of the interesting things about Scratch is that while it was only "officially" supported on OSX and Windows, the user community had figured out that it was just Squeak, and could be run with a Squeak VM on other platforms, particularly Linux.
David> And a thought for the vm-dev list: I don't know if there might be a David> technical solution to this, but it might be possible to use a strategy David> in which the some of the old primitive lookups are preserved (at least David> for the range 207 through 225) if and only if the image format is David> pre-closures. Follow ups to this on vm-only.
Well I did build the official macintosh VM for Scratch, it uses fewer plugins, and has some special handling for "Quit"
Personally I think if they are running scratch without the MIT supplied VM they need to use a VM created before such and such a date.
On 2010-01-16, at 8:33 AM, Randal L. Schwartz wrote:
"David" == David T Lewis lewis@mail.msen.com writes:
David> Question for Subbu: Is this an important issue may affect a large number David> of Scratch users? In other words, are there kids trying to run Scratch, David> and their Scratch image stops working properly after Squeak gets updated David> to use a new VM?
As I recall, one of the interesting things about Scratch is that while it was only "officially" supported on OSX and Windows, the user community had figured out that it was just Squeak, and could be run with a Squeak VM on other platforms, particularly Linux.
David> And a thought for the vm-dev list: I don't know if there might be a David> technical solution to this, but it might be possible to use a strategy David> in which the some of the old primitive lookups are preserved (at least David> for the range 207 through 225) if and only if the image format is David> pre-closures. Follow ups to this on vm-only.
-- Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095 merlyn@stonehenge.com URL:http://www.stonehenge.com/merlyn/ Smalltalk/Perl/Unix consulting, Technical writing, Comedy, etc. etc. See http://methodsandmessages.vox.com/ for Smalltalk and Seaside discussion
-- =========================================================================== John M. McIntosh johnmci@smalltalkconsulting.com Twitter: squeaker68882 Corporate Smalltalk Consulting Ltd. http://www.smalltalkconsulting.com ===========================================================================
On 16.01.2010, at 17:33, Randal L. Schwartz wrote:
"David" == David T Lewis lewis@mail.msen.com writes:
David> Question for Subbu: Is this an important issue may affect a large number David> of Scratch users? In other words, are there kids trying to run Scratch, David> and their Scratch image stops working properly after Squeak gets updated David> to use a new VM?
As I recall, one of the interesting things about Scratch is that while it was only "officially" supported on OSX and Windows, the user community had figured out that it was just Squeak, and could be run with a Squeak VM on other platforms, particularly Linux.
The new 1.4 release is officially supported:
http://info.scratch.mit.edu/Linux_installer
- Bert -
On Saturday 16 January 2010 08:25:02 pm David T. Lewis wrote:
Sorry I was not able to reply earlier. The change was intentional, but the effect on Scratch was not.
Thanks David, for the explanation. Scratch is just a canary in the coal mine. Conventional wisdom lead me to believe that 3.10 to 3.11 would be a normal upgrade path with bugs fixed, code refactored and performance enhanced.
Question for Subbu: Is this an important issue may affect a large number of Scratch users? In other words, are there kids trying to run Scratch, and their Scratch image stops working properly after Squeak gets updated to use a new VM?
My concern is that if 3.11 is not backward compatible with 3.10 and break images this way, people porting projects like Scratch to new platforms will start forking VM for their project. Fixes that go into one fork may not get into the main trunk.
Is this a good time to open up a 4.x branch and push the closure changes into that branch? 3.11 is still on beta so we still have time.
Subbu
vm-dev@lists.squeakfoundation.org