Cairo compiler.

Cairo compiler.

What's Changed

Highlights

• Tuple element access via t.0 syntax. Tuple elements can now be accessed positionally with dot notation (t.0, t.1, …), including nested access, assignments, ref arguments, and access through snapshots. #10111 #10153
• #[panic_with] is deprecated. Using the attribute without opting in via #[feature("deprecated-panic-with")] now emits a warning; prefer plain calculations (now supported in const context) or explicit .expect(...) calls. As part of this, the generated wrapper functions were removed from the corelib — see the breaking change under Corelib below. #10096
• Faster incremental recompilation. Syntax node ids are now kept stable across reparses and plugin-generated files are cached, restoring salsa early cutoff so a structure-preserving edit no longer re-walks the rest of the file — noticeably speeding up the language server. #10105 #10164

Features

• Support tuple element access via t.0 syntax. #10111 #10153
• Deprecated the #[panic_with] attribute; opt in with #[feature("deprecated-panic-with")] to silence the warning. #10096
• Warn (E2201) when an extern type or function is declared outside the core library; suppress with #[allow(extern_outside_corelib)]. #10147
• Support struct-update (..base) syntax in const expressions. #10136
• Evaluate !, &, |, and ^ on bool operands in const contexts. #10212
• Populate MacroPluginMetadata::allowed_features so macro plugins can honor #[feature(...)]. #10094

Bug Fixes

• Reject types that are (or transitively contain) a phantom type when used as values, in signatures, or as array elements, including nested and cyclic cases (E2019), instead of silently compiling or hitting an ICE. #10120 #10169 #10171 #10175
• Disable Felt252Dict construction for illegal value types. #10118
• Emit a diagnostic (E2075) for glob (*) use items in statement position instead of silently accepting them. #10148
• Reject #[default] on a struct member instead of silently ignoring it. #10228
• Fixed derive(Hash)/derive(Serde) codegen for enums, and sanitized the generated hash/serde implementations. #10080 #10117
• Emit derive member bounds for associated-type-path members. #10176
• Validate the quotient in const DivRem to avoid a signed MIN/-1 ICE. #10140
• Substitute the result of generic const function calls with the concrete call-site types. #10143
• Include captured_types in the closure occurs-check. #10086
• Don't ICE on a Deref impl with the wrong number of associated types. #10183
• Don't ICE when an impl provides an associated item of the wrong kind. #10206
• Report every invalid associated-item constraint, not just the first. #10207
• Don't ICE on a wrong generic-argument count reached through a local use alias. #10211
• Report a glob name collision of non-visible items as not-visible rather than ambiguous. #10209
• Apply feature/visibility gating to glob re-exports of generic items. #10217
• Enforce the fixed-size-array size cap on the type form. #10218
• Attribute format!/print! bracket errors to the right macro. #10222
• writeln!(f) with no format string now writes a newline. #10182
• Apply full type-based diagnostics to all parts of a function signature. #10170
• Removed an extra diagnostic emitted for type mismatches on missing. #10121
• Fixed punctuation/newline of bare crate-root diagnostics. #10087
• Skipped-token diagnostic now spans the token, not its leading comment. #10088
• Validate the literal in a negative const generic argument, and anchor literal-validation diagnostics at the token text. #10091 #10103
• Treat //// as a regular comment, not a doc comment. #10107
• Make macro a valid recovery terminal and tree token. #10149
• Stop block recovery at a following control-flow statement. #10227
• Dedup panic_destruct calls for a variable at a shared panic location. #10205
• Normalize storage_base_address_from_felt252 const folding. #10210
• Prune usage after change promotion in loop usage finalization. #10201
• Name macro-call modules by macro name and offset instead of raw call text. #10197
• Close the ] in the FixedSizeArray type short name. #10172
• Fixed a from_trace panic by profiling coupon_call like function_call in the runner. #10081
• Make inline doc links with markup point to their URL. #10151
• Collect executables from modules generated by macro calls. by @integraledelebesgue in #10184

Starknet

• Fully-qualify prelude types in contract codegen. #10137
• Clearer error for a non-ref self constructor. #10223
• Calling meta_tx_v0 no longer crashes cairo test. #10219
• Fixed test-deployment hygiene issues in the Starknet plugin. #10173
• Reject crafted out-of-range type ids instead of panicking when building a Starknet class. #10224
• Validate entry-point signatures before compilation in class-to-casm. #10221
• Validate that entry-point builtins are in canonical order in class-to-casm. #10213

Corelib

• Breaking: removed the generated #[panic_with] wrapper functions (e.g. array_at, u128_from_felt252, u128_sub, u256_sub, and the u*_as_non_zero helpers) in favor of the _try_*/.expect(...) equivalents. #10095
• Made Encode::size_hint more exact. #10108

Formatter

• Sort merged use items via compare_names, and made use merging more consistent. #10123 #10150
• Don't glue a comment to { in an empty block. #10188
• Made cairofmt::skip work properly for additional items. #10220

Optimizations

• Stream the lexer with a lookahead window instead of cloning all tokens up front, reducing peak memory during parsing. #10141
• Keep syntax node ids stable across reparses (canonical roots, kind-keyed child index, parent-relative offsets), restoring salsa early cutoff for structure-preserving edits. #10105 #10190 #10191
• Cache external (plugin-generated) file content in the defs cache. #10164
• Track arrays as a bounded suffix behind a forgotten prefix in equality analysis, and keep tracking remainders popped through it. #10076 #10085
• Avoid cloning blocks and analysis info in inlining and dataflow. #10127
• Made substitute faster on empty substitutions. #10146
• Reduced intermediary string allocations across the compiler. #10124 #10125 #10126

Documentation

• Corrected corelib doc examples and comments: DivRem, keccak_u256s_be_inputs, get_curve_size, egcd's # Panics, Iterator::sum, byte-array example, and misc doc-comment fixes. #10092 https://gi...

Cairo compiler.

Cairo compiler.

Cairo compiler.

Cairo compiler.

Cairo compiler.

Cairo compiler.

What's Changed

Features

• Support Span<T> destructuring via fixed-size array patterns. #9823
• Added support for const calculation of inner variants and lets. #9899
• Implemented sha512 syscall and libfuncs. #9947
• Added sha384 implementation. #9990
• Added struct and enum names and variants to sierra debug info. #9923
• Added type debug info for contracts. #9957

Bug Fixes

• semantic/cache: dedupe const generic args by const value id by @s0mnathh in #9850
• semantic/cache: dedupe FixedSizeArray const size id by @Keemosty12 in #9851
• Include all reachable modules in cache generation via BFS over submodule and macro call edges. #9860
• Report UnsupportedConstant for non-concrete args in eq/ne/not const eval. #9879
• Preventing infinite inlining of cycle functions. #9917
• Fixed ICE on nested const fn in const fn. #9901
• Emit diagnostic on division/modulo by zero in consteval_int by @anon-researchers-123 in #9904
• Reject non-concrete const logical lhs by @Elena343-ai in #9919
• Fixed numeric_value_and_suffix to handle compound suffixes; error on typed literals in consteval_int and test attrs. #9927
• Introduce NumericLiteral type variant for numeric literals. #9929
• Point const-decl literal errors at the value expression. #9930
• Narrow return-type mismatch span to the value-producing expression. #9931
• Validate inferred numeric literal values against their type. #10040
• Skip macro rules with parser-rejected patterns instead of expanding them. #9960
• Avoid panic when an item-scope inline macro lacks an arg-list bracket. #9961
• Don't panic on $(...) without operator in macro calls. #10005
• Preserve escapes in simple panic! macro expansion. #9980
• Correct diagnostic span for write! named placeholders after escapes. #9986
• Correct ClassHash/ContractAddress downcast upper bound off-by-one by @SAY-5 in #9967
• Fixed off-by-one boundary in non-allowed qm31 libfunc. #10009
• Correct NegativeImplLongId::is_fully_concrete. #10010
• Extract generic params from FixedSizeArray size field in negative impl resolution. #10002
• Emit RefutablePattern diagnostic instead of ICE on Span fixed-array let. #9969
• Emit E2008 for generic-type numeric literal suffixes instead of ICE. #9978
• Prevent crash on ? on generics. #9999
• Emit unterminated string error for strings ending with backslash-quote. #9998
• Accept resolver-modifier paths in pattern position. #10039
• Improved missing comma diag. #10063
• Made compile_error! diag not include "s. #10064
• Use all cfg args to extract diagnostics. #10065
• Respect #[cfg] when generating deploy_for_test. #10011
• Fixed suggested crate:: context paths. #10044
• Prevented doubled use self; diagnostic. #10067
• Eliminate spurious E3002 alongside E3001 for moved struct members. #9994
• Give reconstructed structs the original variable's location in E3002. #9996
• Removed extra diag in cases of out of range u256 match. #10006
• early_unsafe_panic must keep side-effecting statements. #10033
• Propagate destruct-impl error in closure lowering. #10007
• Match on @Never with enum_snapshot_match. #10046
• Handle empty enum in Store derive. #10069
• Fixed issue with identical variants on return building. #10056
• Ignoring later fields instead of overriding when getting dup fields. #10053
• Correct n_steps by removing erroneous -1 offsets. #10003
• Include RangeCheck96 in ConstCost::into_full_cost_iter. #10038
• Canonicalize felt252 const-eval values to a unique field-element representative. #9959
• const_values_eq must canonicalize felt252 inside compounds. #10037
• Canonicalize felt252 inside NonZero when matching const patterns. #10058
• Use exclusive upper bound in ExpansionOffset::mapped. #10017
• Include TokenMissing in generated is_missing(). #10020
• Fixed u128_guarantee_mul simulation. #10050
• Fixed implementation of u128s_from_felt simulation. #10068
• Bound test result queue in test runner by @vh0rvath in #9979

Corelib

• Made bounded-int type pub. #9882
• Removed non-safe variant of array-hash. #9988
• Take::nth(usize::MAX) returns None instead of overflowing. #10022
• Make Take::advance_by arithmetic panic-free. #10036
• Add /= and %= for i32/i64/i128 via non-deprecated *Assign. #10027
• Fixed ByteSpan::get OOB empty range. #10051
• Made the panic message more exact for i128_mul. #10042

Formatter

• Sort use self::... items by their full path. #10018
• Avoid usize underflow on over-wide comment prefixes. #10035
• Made all single line comment prevent removing line-breaks. #10045
• Drop trailing empty lines when building the output. #10057

Optimizations

• Non-copy variable forwarding with chain removal. #9905
• Remove cancel_ops phase, subsumed by variable forwarding. #10015
• Using equality analysis to improve match optimization. #9893
• Preallocate lowering pipeline buffers and skip SubStrategy clone. #9995
• Preallocate Sierra emission buffers. #10000
• Memoize per-module feature_config. #9997
• Cache Result/Option EnumIds in CoreInfo, use ID comparison. #9985

Other

• Bumped sierra version. #9972
• Migrated HashMap/HashSet to deterministic Unordered/Ordered wrappers, disallowing std types via clippy. #9953
• dev and rc tags are not marked as latest release. #10030

New Contributors

• @s0mnathh made their first contribution in #9850
• @Keemosty12 made their first contribution in #9851
• @purelualight made their first contribution in #9878
• @mk0walsk made their first contribution in #9881
• @criciss made their first contribution in #9890
• @anon-researchers-123 made their first contribution in #9904
• @serikssonn made their first contribution in #9910
• @jschnelder made their first contribution in #9898
• @box4wangjing made their first contribution in #9918
• @ml0mbardi made their first contribution in #9915
• @knagy2 made their first contribution in #9920
• @ralme1da made their first contribution in https://github.com/starkware-libs/...