fix(nix): set @rpath install_name for librln.dylib on mac

[plopezlpz]

Description

To fix:

  Failed to load plugin: dlopen(.../delivery_module_plugin.dylib):
    Library not loaded: /nix/var/nix/builds/nix-34915-1828854082/source/target/release/deps/librln.dylib

Changes

Pass -Wl,-install_name,@rpath/librln.dylib via RUSTFLAGS during the Cargo build so the correct relocatable reference is set at link time. Linux is unaffected

Testing

• nix build on macOS produces librln.dylib with @rpath/librln.dylib as install_name
• otool -L $out/lib/librln.dylib shows @rpath/librln.dylib

---

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  and propagate errors with ?.
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Linting (mirrors CI)

CI runs clippy across multiple crate/feature combinations. Run the relevant checks locally before pushing:

# Default features - workspace root (rln + utils)
cargo clippy --all-targets --tests --release -- -D warnings

# Stateless feature - from rln/
cd rln && cargo clippy --all-targets --tests --release \
  --features=stateless --no-default-features -- -D warnings

# WASM target - from rln-wasm/
cd rln-wasm && cargo clippy --target wasm32-unknown-unknown \
  --tests --release -- -D warnings

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[NagyZoltanPeter]

Oh, it's great thanks!
I just added this postinstall fix for logos-delivery-module :-D
logos-co/logos-delivery-module#5

[github-actions]

Benchmark for c16fd32

Click to view benchmark

Test	Base	PR	%
FullMerkleTree::::full_depth_gen	10.8±0.23ms	11.8±0.10ms	+9.26%
OptimalMerkleTree::::full_depth_gen	690.3±12.75µs	692.3±6.72µs	+0.29%
Pmtree::delete	50.3±1.08µs	50.6±0.65µs	+0.60%
Pmtree::get	293.7±5.99ns	294.9±8.53ns	+0.41%
Pmtree::get_empty_leaves_indices	8.2±0.25ns	8.4±0.16ns	+2.44%
Pmtree::get_subtree_root	358.7±10.94ns	370.7±8.05ns	+3.35%
Pmtree::override_range	102.3±2.11µs	105.0±1.23µs	+2.64%
Pmtree::set	50.6±0.85µs	50.7±0.80µs	+0.20%
Set/FullMerkleTree::::set/1	510.6±10.75µs	517.3±6.70µs	+1.31%
Set/FullMerkleTree::::set/10	5.2±0.08ms	5.2±0.07ms	0.00%
Set/FullMerkleTree::::set/100	51.5±0.96ms	51.9±0.76ms	+0.78%
Set/FullMerkleTree::::set_range/1	512.1±10.01µs	516.7±9.12µs	+0.90%
Set/FullMerkleTree::::set_range/10	701.4±13.04µs	702.8±13.73µs	+0.20%
Set/FullMerkleTree::::set_range/100	1887.6±43.37µs	1885.5±25.00µs	-0.11%
Set/OptimalMerkleTree::::set/1	516.0±8.45µs	514.8±8.70µs	-0.23%
Set/OptimalMerkleTree::::set/10	5.2±0.05ms	5.2±0.10ms	0.00%
Set/OptimalMerkleTree::::set/100	51.6±0.99ms	52.0±0.80ms	+0.78%
Set/OptimalMerkleTree::::set_range/1	511.0±11.95µs	513.4±6.90µs	+0.47%
Set/OptimalMerkleTree::::set_range/10	712.6±13.45µs	722.0±14.04µs	+1.32%
Set/OptimalMerkleTree::::set_range/100	1813.3±45.21µs	1827.6±30.32µs	+0.79%
rln_finish_partial_proof	66.7±1.17ms	66.7±1.18ms	0.00%
rln_full_proof	183.9±2.65ms	185.4±6.89ms	+0.82%
rln_partial_proof_generation	127.8±1.61ms	128.2±3.39ms	+0.31%

[github-actions]

Benchmark for c16fd32

Click to view benchmark

Test	Base	PR	%
FullMerkleTree::delete	18.0±0.21µs	18.1±0.22µs	+0.56%
FullMerkleTree::get	0.8±0.01ns	0.8±0.01ns	0.00%
FullMerkleTree::get_empty_leaves_indices	981.9±5.62µs	983.9±12.75µs	+0.20%
FullMerkleTree::get_subtree_root	9.9±0.14ns	9.9±0.06ns	0.00%
FullMerkleTree::override_range	1902.5±23.79µs	1896.1±43.72µs	-0.34%
FullMerkleTree::set	8.9±0.09µs	9.0±0.12µs	+1.12%
OptimalMerkleTree::delete	20.7±0.27µs	20.8±0.21µs	+0.48%
OptimalMerkleTree::get	50.6±0.47ns	50.4±0.56ns	-0.40%
OptimalMerkleTree::get_empty_leaves_indices	983.1±9.05µs	982.5±7.54µs	-0.06%
OptimalMerkleTree::get_subtree_root	26.2±0.35ns	26.4±2.07ns	+0.76%
OptimalMerkleTree::override_range	4.0±0.47ms	3.9±0.35ms	-2.50%
OptimalMerkleTree::set	10.6±0.22µs	10.4±0.18µs	-1.89%
poseidon Fr/Array hash/10	140.7±0.18µs 69.4 KElem/sec	N/A	N/A
poseidon Fr/Array hash/100	1508.3±1.34µs 64.7 KElem/sec	N/A	N/A
poseidon Fr/Array hash/1000	15.2±0.01ms 64.2 KElem/sec	N/A	N/A
poseidon Fr/Single hash	13.9±0.02µs 68.4 MElem/sec	N/A	N/A
validate_override_range/FullMerkleTree/override_range/1024	473.1±11.66µs	475.2±19.88µs	+0.44%
validate_override_range/FullMerkleTree/override_range/64	68.9±3.20µs	69.6±3.96µs	+1.02%
validate_override_range/FullMerkleTree/override_range/65536	436.6±3.19ms	441.9±2.63ms	+1.21%
validate_override_range/FullMerkleTree/override_range/8192	8.5±0.05ms	8.7±0.03ms	+2.35%
validate_override_range/OptimalMerkleTree/override_range/1024	641.8±13.23µs	698.5±34.43µs	+8.83%
validate_override_range/OptimalMerkleTree/override_range/64	93.1±6.45µs	92.9±4.74µs	-0.21%
validate_override_range/OptimalMerkleTree/override_range/65536	459.7±4.28ms	461.1±3.36ms	+0.30%
validate_override_range/OptimalMerkleTree/override_range/8192	9.9±0.05ms	9.9±0.04ms	0.00%
validate_override_range/validate_only/1024	8.3±0.12µs	8.3±0.08µs	0.00%
validate_override_range/validate_only/64	358.9±5.06ns	359.9±4.57ns	+0.28%
validate_override_range/validate_only/65536	869.7±10.45µs	869.5±5.44µs	-0.02%
validate_override_range/validate_only/8192	105.9±1.23µs	105.9±1.07µs	0.00%

[jakubgs]

If you grep nixpkgs you can see in most cases RUSTFLAGS is just set directly with needing previous value of RUSTFLAGS.

Suggested change

	buildPhase = ''
	export CARGO_HOME=$TMPDIR/cargo
	'' + pkgs.lib.optionalString pkgs.stdenv.hostPlatform.isDarwin ''
	# Set install_name to @rpath at link time so consumers can dlopen
	# librln.dylib from any location without post-build fixups.
	export RUSTFLAGS="''${RUSTFLAGS:-} -C link-arg=-Wl,-install_name,@rpath/librln.dylib"
	'' + ''
	# Set install_name to @rpath at link time so consumers can dlopen
	# librln.dylib from any location without post-build fixups.
	env.RUSTFLAGS = lib.optionalString stdenv.hostPlatform.isDarwin "-C link-arg=-Wl,-install_name,@rpath/librln.dylib";
	buildPhase = ''
	export CARGO_HOME=$TMPDIR/cargo