CodeSampleX

Sample

getrandom 0.3.4: getrandom 0.3 unsupported backend compiles cleanly but fails non-empty fills with Error::UNSUPPORTED while short-circuiting empty slices to Ok

Verified sample for cargo getrandom 0.3.4: getrandom 0.3 unsupported backend compiles cleanly but fails non-empty fills with Error::UNSUPPORTED while…

sha256:846965d520a96d1f4fc9e250730d0cd97cc28ba1781205f81eee92cf0b08ee85

This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured. How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people. MIT-0

Execution evidence

The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.

Evidence basis
Signed contract pass
Verification receipts
2
Signing keys that built it
2
Declared environment rust linux x64 rust rust cargo

Verification-run environments

Environment Contract Stages Run
rust 1 · linux alpine/x64 · docker ed25519:d91480838ac982c9 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · cargo@1
2026-08-16
rust 1 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · cargo@1
2026-08-18

Case

HOW
Goal
getrandom 0.3 unsupported backend compiles cleanly but fails non-empty fills with Error::UNSUPPORTED while short-circuiting empty slices to Ok
Packages
Symbols
  • getrandom::fill
  • getrandom::fill_uninit
  • getrandom::u32
  • getrandom::u64
  • getrandom::Error::UNSUPPORTED
  • getrandom::Error::raw_os_error
  • getrandom::Error::new_custom
Environment
rust
Created
2026-08-16T09:17:06Z

Contract

  1. assert getrandom compiles cleanly with --cfg getrandom_backend="unsupported"
  2. assert getrandom::fill fails non-empty buffers with Error::UNSUPPORTED
  3. assert getrandom::u32 and u64 fail with Error::UNSUPPORTED
  4. assert getrandom::fill on empty buffer succeeds with Ok
  5. assert getrandom::fill_uninit on empty buffer succeeds with Ok
  6. assert Error::UNSUPPORTED returns None for raw_os_error

Files

  • .cargo/config.toml
  • .gitignore
  • Cargo.lock
  • Cargo.toml
  • NOTES.md
  • csx.json
  • src/lib.rs

Download the source artifact (tar.gz)

Origin Seeder

csx-seed