sp_trie::recorder::Recorder does not live long enough when upgrading para-chain project from polkadot-v0.9.28 to polkadot-v0.9.29

Question

I was upgrading a para chain from polkadot version 0.9.28 to v0.9.29 when I encountered a few suspicious looking build errors originating from deep inside substrate.

To eliminate the risk of some integration error I first built the branch polkadot-v0.9.28 on cumulus repo without any problems then checked out polkadot-v0.9.29 and were able to reproduce the same build error.

cumulus$ cargo build --release
   Compiling sp-keystore v0.12.0 (https://github.com/paritytech/substrate?branch=polkadot-v0.9.29#7c4ac358)
   Compiling sp-state-machine v0.12.0 (https://github.com/paritytech/substrate?branch=polkadot-v0.9.29#7c4ac358)
   Compiling sc-allocator v4.1.0-dev (https://github.com/paritytech/substrate?branch=polkadot-v0.9.29#7c4ac358)
   Compiling sp-rpc v6.0.0 (https://github.com/paritytech/substrate?branch=polkadot-v0.9.29#7c4ac358)
   Compiling librocksdb-sys v0.6.1+6.28.2
   Compiling rococo-runtime v0.9.29 (https://github.com/paritytech/polkadot?branch=release-v0.9.29#94078b44)
   Compiling polkadot-runtime v0.9.29 (https://github.com/paritytech/polkadot?branch=release-v0.9.29#94078b44)
   Compiling kusama-runtime v0.9.29 (https://github.com/paritytech/polkadot?branch=release-v0.9.29#94078b44)
   Compiling polkadot-test-runtime v0.9.29 (https://github.com/paritytech/polkadot?branch=release-v0.9.29#94078b44)
   Compiling cumulus-test-runtime v0.1.0 (/home/simson/nodle/cumulus/test/runtime)
   Compiling cumulus-test-relay-validation-worker-provider v0.1.0 (/home/simson/nodle/cumulus/test/relay-validation-worker-provider)
   Compiling parachain-template-runtime v0.1.0 (/home/simson/nodle/cumulus/parachain-template/runtime)
   Compiling statemine-runtime v2.0.0 (/home/simson/nodle/cumulus/parachains/runtimes/assets/statemine)
   Compiling collectives-polkadot-runtime v1.0.0 (/home/simson/nodle/cumulus/parachains/runtimes/collectives/collectives-polkadot)
   Compiling shell-runtime v0.1.0 (/home/simson/nodle/cumulus/parachains/runtimes/starters/shell)
   Compiling rococo-parachain-runtime v0.1.0 (/home/simson/nodle/cumulus/parachains/runtimes/testing/rococo-parachain)
   Compiling seedling-runtime v0.1.0 (/home/simson/nodle/cumulus/parachains/runtimes/starters/seedling)
   Compiling statemint-runtime v1.0.0 (/home/simson/nodle/cumulus/parachains/runtimes/assets/statemint)
   Compiling contracts-rococo-runtime v0.2.0 (/home/simson/nodle/cumulus/parachains/runtimes/contracts/contracts-rococo)
error: `sp_trie::recorder::Recorder<H>::as_trie_recorder::{opaque#0}<'_>` does not live long enough
   --> /home/simson/.cargo/git/checkouts/substrate-7e08433d4c370a21/7c4ac35/primitives/state-machine/src/trie_backend_essence.rs:181:44
    |
181 |         let recorder = recorder.as_mut().map(|r| r as _);
    |                                                  ^

error: `sp_trie::recorder::Recorder<H>::as_trie_recorder::{opaque#0}<'_>` does not live long enough
   --> /home/simson/.cargo/git/checkouts/substrate-7e08433d4c370a21/7c4ac35/primitives/state-machine/src/trie_backend_essence.rs:219:44
    |
219 |         let recorder = recorder.as_mut().map(|r| r as _);
    |                                                  ^

error: could not compile `sp-state-machine` due to 2 previous errors
warning: build failed, waiting for other jobs to finish...
error: failed to run custom build command for `cumulus-test-relay-validation-worker-provider v0.1.0 (/home/simson/nodle/cumulus/test/relay-validation-worker-provider)`

Caused by:
  process didn't exit successfully: `/home/simson/nodle/cumulus/target/release/build/cumulus-test-relay-validation-worker-provider-12e504f71174b33a/build-script-build` (exit status: 1)

Any ideas what could be the problem here and how to solve it?

Answer 1

Yeah that is a recent breakage. Here is the commit that fixed it on master. I think this is some regression in rustc: https://github.com/rust-lang/rust/issues/100544