Stream: git-wasmtime

Topic: wasmtime / PR #11255 More table safety improvements

Wasmtime GitHub notifications bot (Jul 16 2025 at 16:07):

alexcrichton requested pchickey for a review on PR #11255.

Wasmtime GitHub notifications bot (Jul 16 2025 at 16:07):

alexcrichton opened PR #11255 from alexcrichton:more-safer-tables to bytecodealliance:main:

This is some more progress on #11179 aimed at improving the safety of management of tables internally within Wasmtime:

• Instance::table_index is removed as it can be replaced with data stored directly in the VMTableImport now.
• Instance::get_table now returns &mut Table
• Instance::get_defined_table_with_lazy_init now returns &mut Table
• Instance::with_defined_table_index_and_instance now directly returns DefinedTableIndex plus Pin<&mut Instance>, codifying the ability to "laterally move" between instances.
• Instance::table_init_segment was refactored to "take" the tables during initialization and replace them afterwards, resolving the split borrow issue and removing an unsafe block in the function.

cc #11179

<!--
Please make sure you include the following information:

• If this work has been discussed elsewhere, please include a link to that
  conversation. If it was discussed in an issue, just mention "issue #...".

• Explain why this change is needed. If the details are in an issue already,
  this can be brief.

Our development process is documented in the Wasmtime book:
https://docs.wasmtime.dev/contributing-development-process.html

Please ensure all communication follows the code of conduct:
https://github.com/bytecodealliance/wasmtime/blob/main/CODE_OF_CONDUCT.md
-->

Wasmtime GitHub notifications bot (Jul 16 2025 at 16:07):

alexcrichton requested wasmtime-core-reviewers for a review on PR #11255.

Wasmtime GitHub notifications bot (Jul 16 2025 at 16:35):

pchickey submitted PR review.

Wasmtime GitHub notifications bot (Jul 16 2025 at 18:43):

alexcrichton requested fitzgen for a review on PR #11255.

Wasmtime GitHub notifications bot (Jul 16 2025 at 18:43):

alexcrichton requested wasmtime-compiler-reviewers for a review on PR #11255.

Wasmtime GitHub notifications bot (Jul 16 2025 at 18:43):

alexcrichton updated PR #11255.

Wasmtime GitHub notifications bot (Jul 16 2025 at 18:44):

alexcrichton commented on PR #11255:

The Miri violation of stacked borrows is I believe legitimate, so I've added a new commit which improves the safety situation around Table::copy. @pchickey mind reviewing that new commit as well?

Wasmtime GitHub notifications bot (Jul 16 2025 at 19:11):

alexcrichton updated PR #11255.

Wasmtime GitHub notifications bot (Jul 16 2025 at 22:12):

alexcrichton edited PR #11255:

This is some more progress on #11179 aimed at improving the safety of management of tables internally within Wasmtime:

• Instance::table_index is removed as it can be replaced with data stored directly in the VMTableImport now.
• Instance::get_table now returns &mut Table
• Instance::get_defined_table_with_lazy_init now returns &mut Table
• Instance::with_defined_table_index_and_instance now directly returns DefinedTableIndex plus Pin<&mut Instance>, codifying the ability to "laterally move" between instances.
• Instance::table_init_segment was refactored to "take" the tables during initialization and replace them afterwards, resolving the split borrow issue and removing an unsafe block in the function.

Closes #11179

<!--
Please make sure you include the following information:

• If this work has been discussed elsewhere, please include a link to that
  conversation. If it was discussed in an issue, just mention "issue #...".

• Explain why this change is needed. If the details are in an issue already,
  this can be brief.

Our development process is documented in the Wasmtime book:
https://docs.wasmtime.dev/contributing-development-process.html

Please ensure all communication follows the code of conduct:
https://github.com/bytecodealliance/wasmtime/blob/main/CODE_OF_CONDUCT.md
-->

Wasmtime GitHub notifications bot (Jul 16 2025 at 22:13):

alexcrichton commented on PR #11255:

I've also flagged this as closing https://github.com/bytecodealliance/wasmtime/issues/11179 as this resolves all remaining bits I know of there, and I otherwise split out https://github.com/bytecodealliance/wasmtime/issues/11262 from that issue.

Wasmtime GitHub notifications bot (Jul 17 2025 at 15:25):

pchickey submitted PR review.

Wasmtime GitHub notifications bot (Jul 17 2025 at 17:40):

alexcrichton merged PR #11255.

Last updated: Dec 06 2025 at 07:03 UTC