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oriziclaude
orizi
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claude
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bug fix(semantic): Validate quotient in const DivRem to avoid signed MIN/-1 ICE.
The const-eval path for `DivRem::div_rem` stored the quotient without validating it against the input type's range. For signed `iN::MIN / -1` the quotient is `2^(N-1)` (= `iN::MAX + 1`), which is unrepresentable in `iN`; the out-of-range value was silently stored and later caused an ICE in sierra type-specialization (`Got failure while specializing type Const<i8, 128>`). Now the quotient is validated via `validate_literal`, emitting a clean E2008 LiteralError::OutOfRange — matching the `/` operator path. Fixes #10132. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Lines changed: 25 additions & 9 deletions

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‎Cargo.lock‎

Lines changed: 1 addition & 0 deletions
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‎crates/cairo-lang-semantic/Cargo.toml‎

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Original file line numberDiff line numberDiff line change
@@ -26,6 +26,7 @@ id-arena.workspace = true
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indoc.workspace = true
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itertools = { workspace = true, default-features = true }
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num-bigint = { workspace = true, default-features = true }
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num-integer = { workspace = true, default-features = true }
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num-traits = { workspace = true, default-features = true }
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postcard.workspace = true
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salsa.workspace = true

‎crates/cairo-lang-semantic/src/expr/test_data/constant‎

Lines changed: 12 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -211,6 +211,9 @@ const VALID_LE: () = assert(1_usize <= 1);
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const VALID_GT: () = assert(2_usize > 1);
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const VALID_GE: () = assert(1_usize >= 1);
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const VALID_DIVREM: () = assert(DivRem::div_rem(5_u8, 2) == (2, 1));
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// The quotient of signed `MIN / -1` overflows the type, and should emit a clean diagnostic
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// rather than silently storing an out-of-range value (which later ICEs in sierra-gen).
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const DIVREM_SIGNED_MIN_OVERFLOW: (i8, i8) = DivRem::div_rem(-128_i8, -1);
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const MATCH_VALUE: () = assert(match 1_u8 {
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_ => 1,
@@ -300,22 +303,27 @@ note: In `test::assert`:
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core::panic_with_felt252('failed assertion')
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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error[E2008]: The value does not fit within the range of type core::integer::i8.
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--> lib.cairo:69:46
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const DIVREM_SIGNED_MIN_OVERFLOW: (i8, i8) = DivRem::div_rem(-128_i8, -1);
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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error[E2129]: Constant calculation depth exceeded.
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--> lib.cairo:92:43
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--> lib.cairo:95:43
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const FUNC_CALC_STACK_EXCEEDED: felt252 = call_myself();
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^^^^^^^^^^^^^
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error[E2130]: Failed to calculate constant.
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--> lib.cairo:99:37
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--> lib.cairo:102:37
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const NON_ZERO_ZERO: NonZero<u64> = my_unwrap(ZERO.try_into());
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^^^^^^^^^^^^^^^^^^^^^^^^^^
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note: In `test::my_unwrap::<core::zeroable::NonZero::<core::integer::u64>>`:
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--> lib.cairo:105:17
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--> lib.cairo:108:17
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None => core::panic_with_felt252('bad value'),
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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error[E2128]: Failed to calculate constant.
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--> lib.cairo:111:9
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--> lib.cairo:114:9
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core::panic_with_felt252('should fail')
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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‎crates/cairo-lang-semantic/src/items/constant.rs‎

Lines changed: 11 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -22,6 +22,7 @@ use cairo_lang_utils::unordered_hash_set::UnorderedHashSet;
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use cairo_lang_utils::{Intern, define_short_id, extract_matches, require, try_extract_matches};
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use itertools::Itertools;
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use num_bigint::BigInt;
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use num_integer::Integer;
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use num_traits::{ToPrimitive, Zero};
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use salsa::Database;
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use starknet_types_core::felt::{CAIRO_PRIME_BIGINT, Felt as Felt252};
@@ -931,12 +932,17 @@ impl<'a, 'r, 'mt> ConstantEvaluateContext<'a, 'r, 'mt> {
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id if id == self.ge_fn => return bool_value(args[0].v >= args[1].v),
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id if id == self.div_rem_fn => {
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// No need for non-zero check as this is type checked to begin with.
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// Also results are always in the range of the input type, so `unwrap`s are ok.
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let (q, r) = args[0].v.div_rem(&args[1].v);
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let ty = args[0].ty;
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// The quotient may overflow for signed `MIN / -1`, so it must be validated.
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if let Err(err) = validate_literal(db, ty, &q) {
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return to_missing(self.diagnostics.report(
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expr.stable_ptr.untyped(),
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SemanticDiagnosticKind::LiteralError(err),
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));
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}
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return ConstValue::Struct(
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vec![
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ConstValueId::from_int(db, args[0].ty, &(&args[0].v / &args[1].v)),
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ConstValueId::from_int(db, args[0].ty, &(&args[0].v % &args[1].v)),
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],
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vec![ConstValueId::from_int(db, ty, &q), ConstValueId::from_int(db, ty, &r)],
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expr.ty,
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)
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.intern(db);

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