Derive encode/decode compile error[E0308]: mismatched types

[dlamar228]

Description

Encode and decode macro in parity-scale-codec-derive 3.7.1 fails to compile following type:

#[repr(u32)]
#[derive(parity_scale_codec::Encode, parity_scale_codec::Decode)]
enum DigestItemType {
    Other = 0u32,
    Consensus = 4u32,
    Seal = 5u32,
    PreRuntime = 6u32,
    RuntimeEnvironmentUpdated = 8u32,
}

Logs

cargo c Compiling proc-macro2 v1.0.93 Compiling unicode-ident v1.0.15 Compiling equivalent v1.0.1 Compiling hashbrown v0.15.2 Compiling rustversion v1.0.19 Compiling winnow v0.6.24 Compiling toml_datetime v0.6.8 Compiling unicode-xid v0.2.6 Compiling serde v1.0.217 Checking byte-slice-cast v1.2.2 Checking arrayvec v0.7.6 Compiling indexmap v2.7.1 Compiling quote v1.0.38 Compiling parity-scale-codec v3.7.1 Compiling syn v2.0.96 Compiling const_format_proc_macros v0.2.34 Checking const_format v0.2.34 Compiling toml_edit v0.22.22 Compiling proc-macro-crate v3.2.0 Compiling impl-trait-for-tuples v0.2.3 Compiling parity-scale-codec-derive v3.7.1 Checking test-sub v0.1.0 (/media/ubuntu/porn30/asd/kuber-atleta/test-sub) error[E0308]: mismatched types --> src/main.rs:8:13 | 8 | Other = 0u32, | ^^^^ expected `usize`, found `u32` | help: change the type of the numeric literal from `u32` to `usize` | 8 | Other = 0usize, | ~~~~~

error[E0308]: mismatched types
--> src/main.rs:9:17
|
9 | Consensus = 4u32,
| ^^^^ expected usize, found u32
|
help: change the type of the numeric literal from u32 to usize
|
9 | Consensus = 4usize,
| ~~~~~

error[E0308]: mismatched types
--> src/main.rs:10:12
|
10 | Seal = 5u32,
| ^^^^ expected usize, found u32
|
help: change the type of the numeric literal from u32 to usize
|
10 | Seal = 5usize,
| ~~~~~

error[E0308]: mismatched types
--> src/main.rs:11:18
|
11 | PreRuntime = 6u32,
| ^^^^ expected usize, found u32
|
help: change the type of the numeric literal from u32 to usize
|
11 | PreRuntime = 6usize,
| ~~~~~

error[E0308]: mismatched types
--> src/main.rs:12:33
|
12 | RuntimeEnvironmentUpdated = 8u32,
| ^^^^ expected usize, found u32
|
help: change the type of the numeric literal from u32 to usize
|
12 | RuntimeEnvironmentUpdated = 8usize,
| ~~~~~

For more information about this error, try rustc --explain E0308.
error: could not compile test-sub (bin "test-sub") due to 10 previous errors


Working version

parity-scale-codec = { version = "=3.6.12", features = ["derive"] }
parity-scale-codec-derive = "=3.6.12"

[serban300]

Seems caused by this PR: #653 . Investigating why.

[pkhry]

It's because of the consteval check on the literals, thr code expects usize, but got u32 instead. Ie we need to do a check for syn::LitNum for thr suffix and assign type accordingly, otherwise use usize

[jsdw]

I believe I have a solution for this; will open a quick PR to check.

I'd suggest yanking this release now (if not done already) and doing a new one with the fix merged.

[serban300]

Ok, thank you ! Will yank this release.

[jsdw]

I hope this PR will fix it: #687

[serban300]

@dlamar228 thank you for the report ! The fix was merged and we published release 3.7.2 . Please let us know if any other issue arises