'Stack offset of 7256 exceeded max offset of 4096' from Anchor try_accounts — Box your accounts

Symptom: cargo build-sbf / anchor build completes but prints, for several functions, Function _ZN...try_accounts... Stack offset of N exceeded max offset of 4096 by M bytes, please minimize large stack variables. The mangled names point at Anchor's generated try_accounts for your #[derive(Accounts)] structs, not at code you wrote.

Cause: SBF gives each function a 4 KB stack frame. Anchor's account-validation code materialises every account in the struct in one frame, so wide Accounts structs (many PDAs, init constraints, zero_copy) overflow it. The build still succeeds, which is the trap: these are warnings, but the overflowing frame can corrupt data or abort at runtime, so do not ship them. Anchor's fix (force-inlining parts of try_accounts, coral-xyz/anchor#2939) landed alongside Agave 2.x; with solana-program 1.18 and platform-tools 1.41 not all offending frames are even reported at compile time, which is why a program can pass a clean build and still fail on chain. platform-tools 1.42 reports them all.

Concrete mitigations that work without upgrading: wrap large accounts as Box<Account<'info, T>> / Box<InterfaceAccount<'info, Mint>> so the payload lives on the heap, split one fat instruction into several, and move rarely used accounts into remaining_accounts.

If you also hit the trait bound streamflow_sdk::cpi::accounts::Update: ToAccountInfos is not satisfied ... perhaps two different versions of crate anchor_lang are being used, that is a separate symptom of the same fix attempt: pulling anchor-lang from git while a dependency SDK links a crates.io anchor-lang. Pin both to one released version rather than mixing git and registry sources.

Version context: this analysis is from the Anchor 0.30/solana 1.18 era. On Agave 2.x with Anchor 0.31+ most of these frames are gone; if you still see them, the Box/split advice remains the fix.

Source: adapted from a Stack Exchange answer by Jonas H. (question by Abhishek Faliya), https://solana.stackexchange.com/questions/16443/error-function-stack-offset-of-7256-exceeded-max-offset-of-4096-by-3160-bytes — CC BY-SA 4.0