Skip to content

Add a warning about relying on runtime bounds validation #112

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
someone235 merged 1 commit into from
Apr 28, 2026
Merged

Add a warning about relying on runtime bounds validation #112

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 3 additions & 1 deletion docs/TUTORIAL.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -470,7 +470,7 @@ contract ForLoop() {
}
```

The loop variable `i` takes values from `start` to `end - 1` (exclusive end). The range length must not exceed the compile-time unroll bound, so `end - start <= MAX_ITERATIONS` must hold. If the compiler can prove that a constant range exceeds the bound, compilation fails. For runtime bounds, the generated script checks the same condition before entering the loop and fails if the provided range is too large.
The loop variable `i` takes values from `start` to `end - 1` (exclusive end). The range length must not exceed the compile-time unroll bound, so `end - start <= MAX_ITERATIONS` must hold. If the compiler can prove that a constant range exceeds the bound, compilation fails. For runtime bounds, the generated script currently checks the same condition before entering the loop and fails if the provided range is too large.

If `start >= end`, the loop performs no iterations. Otherwise, the compiler emits exactly `MAX_ITERATIONS` guarded iterations, and each guarded iteration runs only while the current loop variable is still below `end`.

Expand Down Expand Up @@ -498,6 +498,8 @@ contract RuntimeLoopFailure() {
}
```

**Warning:** The runtime assertion is a current compiler behavior and may be removed in a later version. Do not rely on its existence as a stable validation mechanism; validate runtime loop bounds explicitly when the contract depends on that validation.

---

## Working with Data
Expand Down