Bump MSRV to rustc 1.85

We generally align our MSRV with Debian's stable channel. Debian 13
'Trixie' was just released, shipping rustc 1.85. We therefore bump our
MSRV on the `main` branch here.

Author: tnull

.github/workflows/build.yml

@@ -31,10 +31,10 @@ jobs:
       fail-fast: false
       matrix:
         platform: [ self-hosted, windows-latest, macos-latest ]
-        toolchain: [ stable, beta, 1.63.0 ] # 1.63.0 is the MSRV for all crates but `lightning-transaction-sync`.
+        toolchain: [ stable, beta, 1.85.0 ] # 1.85.0 is the MSRV for all crates but `lightning-transaction-sync`.
         exclude:
           - platform: windows-latest
-            toolchain: 1.63.0
+            toolchain: 1.85.0
           - platform: windows-latest
             toolchain: beta
           - platform: macos-latest
@@ -60,7 +60,7 @@ jobs:
           shellcheck ci/*.sh -aP ci
           shellcheck contrib/*.sh -aP contrib
       - name: Set RUSTFLAGS to deny warnings
-        if: "matrix.toolchain == '1.63.0'"
+        if: "matrix.toolchain == '1.85.0'"
         run: echo "RUSTFLAGS=-D warnings" >> "$GITHUB_ENV"
       - name: Run CI script
         shell: bash # Default on Winblows is powershell
@@ -71,7 +71,7 @@ jobs:
       fail-fast: false
       matrix:
         platform: [ ubuntu-latest, macos-latest ]
-        toolchain: [ stable, beta, 1.75.0 ] # 1.75.0 is the MSRV for `lightning-transaction-sync`.
+        toolchain: [ stable, beta, 1.85.0 ]
     runs-on: ${{ matrix.platform }}
     steps:
       - name: Checkout source code
@@ -80,7 +80,7 @@ jobs:
         run: |
           curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --profile=minimal --default-toolchain ${{ matrix.toolchain }}
       - name: Set RUSTFLAGS to deny warnings
-        if: "matrix.toolchain == '1.75.0'"
+        if: "matrix.toolchain == '1.85.0'"
         run: echo "RUSTFLAGS=-D warnings" >> "$GITHUB_ENV"
       - name: Enable caching for bitcoind
         id: cache-bitcoind
@@ -236,17 +236,13 @@ jobs:
   fuzz:
     runs-on: self-hosted
     env:
-      TOOLCHAIN: 1.63
+      TOOLCHAIN: 1.85
     steps:
       - name: Checkout source code
         uses: actions/checkout@v4
       - name: Install Rust ${{ env.TOOLCHAIN }} toolchain
         run: |
           curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --profile=minimal --default-toolchain ${{ env.TOOLCHAIN }}
-      - name: Pin the regex dependency
-        run: |
-          cd fuzz && cargo update -p regex --precise "1.9.6" --verbose
-          cd write-seeds && cargo update -p regex --precise "1.9.6" --verbose
       - name: Sanity check fuzz targets on Rust ${{ env.TOOLCHAIN }}
         run: |
           cd fuzz
@@ -275,7 +271,7 @@ jobs:
   rustfmt:
     runs-on: ubuntu-latest
     env:
-      TOOLCHAIN: 1.63.0
+      TOOLCHAIN: 1.85.0
     steps:
       - name: Checkout source code
         uses: actions/checkout@v4

CONTRIBUTING.md

@@ -88,7 +88,7 @@ be covered by functional tests.
 When refactoring, structure your PR to make it easy to review and don't
 hesitate to split it into multiple small, focused PRs.
 
-The Minimum Supported Rust Version (MSRV) currently is 1.63.0 (enforced by
+The Minimum Supported Rust Version (MSRV) currently is 1.85.0 (enforced by
 our GitHub Actions). We support reading serialized LDK objects written by any
 version of LDK 0.0.99 and above. We support LDK versions 0.0.113 and above
 reading serialized LDK objects written by modern LDK. Any expected issues with
@@ -124,7 +124,7 @@ display fine at any tab-length display setting. We use `rustfmt` to establish
 uniform coding standards throughout the codebase. Please run
 
 ```bash
-cargo +1.63.0 fmt
+cargo +1.85.0 fmt
 ```
 
 before committing and pushing any changes, as compliance will also be checked

ci/check-lint.sh

@@ -45,7 +45,6 @@ CLIPPY() {
 		-A clippy::len_without_is_empty \
 		-A clippy::len_zero \
 		-A clippy::let_and_return \
-		-A clippy::manual_div_ceil `# to be removed once we hit MSRV 1.73.0` \
 		-A clippy::manual_filter \
 		-A clippy::manual_map \
 		-A clippy::manual_memcpy \
@@ -104,9 +103,7 @@ CLIPPY() {
 		-A clippy::unnecessary_unwrap \
 		-A clippy::unused_unit \
 		-A clippy::useless_conversion \
-		-A clippy::unnecessary_map_or `# to be removed once we hit MSRV 1.70` \
 		-A clippy::manual_repeat_n `# to be removed once we hit MSRV 1.86` \
-		-A clippy::io_other_error `# to be removed once we hit MSRV 1.74` \
 		-A clippy::uninlined-format-args
 }
 

ci/ci-tests.sh

@@ -1,41 +1,18 @@
 #!/bin/bash
 set -eox pipefail
 
-RUSTC_MINOR_VERSION=$(rustc --version | awk '{ split($2,a,"."); print a[2] }')
+# Currently unused as we don't have to pin anything for MSRV:
+#RUSTC_MINOR_VERSION=$(rustc --version | awk '{ split($2,a,"."); print a[2] }')
 
 # Some crates require pinning to meet our MSRV even for our downstream users,
 # which we do here.
 # Further crates which appear only as dev-dependencies are pinned further down.
 function PIN_RELEASE_DEPS {
-	# Starting with version 1.39.0, the `tokio` crate has an MSRV of rustc 1.70.0
-	[ "$RUSTC_MINOR_VERSION" -lt 70 ] && cargo update -p tokio --precise "1.38.1" --verbose
-
 	return 0 # Don't fail the script if our rustc is higher than the last check
 }
 
 PIN_RELEASE_DEPS # pin the release dependencies in our main workspace
 
-# Starting with version 1.10.0, the `regex` crate has an MSRV of rustc 1.65.0.
-[ "$RUSTC_MINOR_VERSION" -lt 65 ] && cargo update -p regex --precise "1.9.6" --verbose
-
-# The addr2line v0.21 crate (a dependency of `backtrace` starting with 0.3.69) relies on rustc 1.65
-[ "$RUSTC_MINOR_VERSION" -lt 65 ] && cargo update -p backtrace --precise "0.3.68" --verbose
-
-# The once_cell v1.21.0 crate (a dependency of `proptest`) relies on rustc 1.70
-[ "$RUSTC_MINOR_VERSION" -lt 70 ] && cargo update -p once_cell --precise "1.20.3" --verbose
-
-# proptest 1.3.0 requires rustc 1.64.0
-[ "$RUSTC_MINOR_VERSION" -lt 64 ] && cargo update -p proptest --precise "1.2.0" --verbose
-
-# parking_lot 0.12.4 requires rustc 1.64.0
-[ "$RUSTC_MINOR_VERSION" -lt 64 ] && cargo update -p parking_lot --precise "0.12.3" --verbose
-
-# parking_lot_core 0.9.11 requires rustc 1.64.0
-[ "$RUSTC_MINOR_VERSION" -lt 64 ] && cargo update -p parking_lot_core --precise "0.9.10" --verbose
-
-# lock_api 0.4.13 requires rustc 1.64.0
-[ "$RUSTC_MINOR_VERSION" -lt 64 ] && cargo update -p lock_api --precise "0.4.12" --verbose
-
 export RUST_BACKTRACE=1
 
 echo -e "\n\nChecking the workspace, except lightning-transaction-sync."
@@ -64,7 +41,6 @@ cargo test --verbose --color always
 
 echo -e "\n\nTesting upgrade from prior versions of LDK"
 pushd lightning-tests
-[ "$RUSTC_MINOR_VERSION" -lt 65 ] && cargo update -p regex --precise "1.9.6" --verbose
 cargo test
 popd
 

ci/ci-tx-sync-tests.sh

@@ -1,7 +1,8 @@
 #!/bin/bash
 set -eox pipefail
 
-RUSTC_MINOR_VERSION=$(rustc --version | awk '{ split($2,a,"."); print a[2] }')
+# Currently unused as we don't have to pin anything for MSRV:
+#RUSTC_MINOR_VERSION=$(rustc --version | awk '{ split($2,a,"."); print a[2] }')
 
 pushd lightning-transaction-sync
 
@@ -14,12 +15,6 @@ function PIN_RELEASE_DEPS {
 
 PIN_RELEASE_DEPS # pin the release dependencies
 
-# Starting with version 0.5.11, the `home` crate has an MSRV of rustc 1.81.0.
-[ "$RUSTC_MINOR_VERSION" -lt 81 ] && cargo update -p home --precise "0.5.9" --verbose
-
-# Starting with version 1.2.0, the `idna_adapter` crate has an MSRV of rustc 1.81.0.
-[ "$RUSTC_MINOR_VERSION" -lt 81 ] && cargo update -p idna_adapter --precise "1.1.0" --verbose
-
 export RUST_BACKTRACE=1
 
 echo -e "\n\nChecking Transaction Sync Clients with features."

lightning-background-processor/src/lib.rs

@@ -259,7 +259,8 @@ impl<
 		G,
 		&'a (dyn UtxoLookup + Send + Sync),
 		L,
-	> where
+	>
+where
 	L::Target: Logger,
 {
 	/// Initializes a new [`GossipSync::Rapid`] variant.
@@ -276,7 +277,8 @@ impl<'a, L: Deref>
 		&'a NetworkGraph<L>,
 		&'a (dyn UtxoLookup + Send + Sync),
 		L,
-	> where
+	>
+where
 	L::Target: Logger,
 {
 	/// Initializes a new [`GossipSync::None`] variant.

lightning/src/ln/channel.rs

@@ -8671,23 +8671,25 @@ where
 		log_trace!(logger, "Regenerating latest commitment update in channel {} with{} {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
 				&self.context.channel_id(), if update_fee.is_some() { " update_fee," } else { "" },
 				update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len(), update_fail_malformed_htlcs.len());
-		let commitment_signed =
-			if let Ok(update) = self.send_commitment_no_state_update(logger) {
-				if self.context.signer_pending_commitment_update {
-					log_trace!(
-						logger,
-						"Commitment update generated: clearing signer_pending_commitment_update"
-					);
-					self.context.signer_pending_commitment_update = false;
-				}
-				update
-			} else {
-				if !self.context.signer_pending_commitment_update {
-					log_trace!(logger, "Commitment update awaiting signer: setting signer_pending_commitment_update");
-					self.context.signer_pending_commitment_update = true;
-				}
-				return Err(());
-			};
+		let commitment_signed = if let Ok(update) = self.send_commitment_no_state_update(logger) {
+			if self.context.signer_pending_commitment_update {
+				log_trace!(
+					logger,
+					"Commitment update generated: clearing signer_pending_commitment_update"
+				);
+				self.context.signer_pending_commitment_update = false;
+			}
+			update
+		} else {
+			if !self.context.signer_pending_commitment_update {
+				log_trace!(
+					logger,
+					"Commitment update awaiting signer: setting signer_pending_commitment_update"
+				);
+				self.context.signer_pending_commitment_update = true;
+			}
+			return Err(());
+		};
 		Ok(msgs::CommitmentUpdate {
 			update_add_htlcs,
 			update_fulfill_htlcs,

lightning/src/ln/channelmanager.rs

@@ -8181,7 +8181,8 @@ where
 		ComplFunc: FnOnce(
 			Option<u64>,
 			bool,
-		) -> (Option<MonitorUpdateCompletionAction>, Option<RAAMonitorUpdateBlockingAction>),
+		)
+			-> (Option<MonitorUpdateCompletionAction>, Option<RAAMonitorUpdateBlockingAction>),
 	>(
 		&self, prev_hop: HTLCPreviousHopData, payment_preimage: PaymentPreimage,
 		payment_info: Option<PaymentClaimDetails>, attribution_data: Option<AttributionData>,
@@ -8219,7 +8220,8 @@ where
 		ComplFunc: FnOnce(
 			Option<u64>,
 			bool,
-		) -> (Option<MonitorUpdateCompletionAction>, Option<RAAMonitorUpdateBlockingAction>),
+		)
+			-> (Option<MonitorUpdateCompletionAction>, Option<RAAMonitorUpdateBlockingAction>),
 	>(
 		&self, prev_hop: HTLCClaimSource, payment_preimage: PaymentPreimage,
 		payment_info: Option<PaymentClaimDetails>, attribution_data: Option<AttributionData>,

lightning/src/ln/functional_test_utils.rs

@@ -1952,7 +1952,7 @@ pub fn do_check_spends<F: Fn(&bitcoin::transaction::OutPoint) -> Option<TxOut>>(
 		total_value_out += output.value.to_sat();
 	}
 	let min_fee = (tx.weight().to_wu() as u64 + 3) / 4; // One sat per vbyte (ie per weight/4, rounded up)
-													// Input amount - output amount = fee, so check that out + min_fee is smaller than input
+													 // Input amount - output amount = fee, so check that out + min_fee is smaller than input
 	assert!(total_value_out + min_fee <= total_value_in);
 	tx.verify(get_output).unwrap();
 }

lightning/src/ln/functional_tests.rs

@@ -1223,7 +1223,7 @@ pub fn test_justice_tx_htlc_timeout() {
 		revoked_local_txn[1].input[0].witness.last().unwrap().len(),
 		OFFERED_HTLC_SCRIPT_WEIGHT
 	); // HTLC-Timeout
-   // Revoke the old state
+	// Revoke the old state
 	claim_payment(&nodes[0], &[&nodes[1]], payment_preimage_3);
 
 	{
@@ -6635,7 +6635,7 @@ pub fn test_announce_disable_channels() {
 		match e {
 			MessageSendEvent::BroadcastChannelUpdate { ref msg } => {
 				assert_eq!(msg.contents.channel_flags & (1 << 1), 1 << 1); // The "channel disabled" bit should be set
-														   // Check that each channel gets updated exactly once
+															   // Check that each channel gets updated exactly once
 				if chans_disabled
 					.insert(msg.contents.short_channel_id, msg.contents.timestamp)
 					.is_some()