padlock for VS Code
The lint pass for struct memory layout — finds padding waste, false sharing, and cache locality problems in C, C++, Rust, and Go, shown directly in the Problems panel.
What it does
When you save a supported file, padlock runs in the background and populates the Problems panel with layout findings. No squiggles, no interruptions — just findings waiting when you want them.
WARNING Connection: 10B wasted (41%). Run 'padlock explain' for full layout. connection.rs line 4
WARNING Connection: reordering fields saves 8B (24B → 16B). Use 'padlock: Apply fix'. connection.rs line 4
Requirements
padlock must be installed and on your PATH:
cargo install padlock-cli
Commands
| Command |
Description |
padlock: Analyze current file |
Run analysis on the open file |
padlock: Analyze workspace |
Run analysis across the entire workspace |
padlock: Apply fix (reorder fields) |
Reorder fields in the current file to the optimal layout |
padlock: Clear findings |
Remove all padlock diagnostics from the Problems panel |
Settings
| Setting |
Default |
Description |
padlock.runOnSave |
true |
Analyze automatically on file save |
padlock.severity |
"high" |
Minimum severity: high, medium, or low |
padlock.executable |
"padlock" |
Path to the padlock binary |
padlock.extraArgs |
[] |
Extra arguments passed to every analysis run |
Example: only show High findings, use a custom binary path
{
"padlock.severity": "high",
"padlock.executable": "/home/user/.cargo/bin/padlock",
"padlock.extraArgs": ["--min-size", "16"]
}
Severity mapping
padlock findings appear in the Problems panel with the following VS Code severity levels:
| padlock severity |
VS Code level |
Icon |
| High |
Warning |
⚠ yellow |
| Medium |
Information |
ℹ blue |
| Low |
Hint |
subtle underline |
Layout issues are never shown as errors — they don't prevent your code from compiling.
- CI: use the padlock GitHub Action to block PRs on High findings
- Pre-commit: add padlock to your git hooks to catch issues before they reach the repo
- Runtime profiling: use padlock findings as a guide for where to focus with
perf c2c or VTune
