hy-check(shape): named_shape_depth and call_shape omit complex64 and complex128, falsely rejecting sendable values with HYB-E3005 #4000

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1. dukenordj-rgb commented on Nov 7, 2026

   

   dukenordj-rgb

   on Nov 7, 2026

   Contributor

   More actions

   Root Cause Analysis

   Under SPEC §9.2, complex64 and complex128 (along with aliases c64 and c128) are primitive copy-by-value numeric types and must be classified as unconditionally sendable (TypeShape::Primitive).

   The hy-check shape analysis pass fails to register complex primitive types across three helper methods in compiler/crates/hy-check/src/shape.rs:

   1. Checker::named_shape_depth: Omits complex64, complex128, c64, and c128 from primitive type string matching, defaulting named type shapes to TypeShape::Unknown.
   2. Checker::call_shape: Omits constructor invocations for complex64, complex128, as well as built-in functions complex, real, and imag, returning TypeShape::Unknown for built-in expressions.
   3. Checker::receiver_type_params: Omits complex64 and complex128 from the primitive non-generic filter set.

   Because sendability.rs enforces rule O4.9 (fail-closed on TypeShape::Unknown), any complex scalar, struct embedding complex fields, or channel carrying complex types is classified as unproven, triggering a false-positive compilation failure with HYB-E3005.

   ---

   Patch Snippet

   --- a/compiler/crates/hy-check/src/shape.rs
   +++ b/compiler/crates/hy-check/src/shape.rs
   @@ -112,6 +112,7 @@ impl<'a> Checker<'a> {
                "int" | "i8" | "i16" | "i32" | "i64" |
                "uint" | "u8" | "u16" | "u32" | "u64" | "uintptr" |
                "float32" | "float64" | "bool" | "byte" | "rune" |
   +            "complex64" | "complex128" | "c64" | "c128" =>
                    Some(TypeShape::Primitive),
                _ => None,
            }
   @@ -245,6 +246,8 @@ impl<'a> Checker<'a> {
            match callee {
                "int" | "uint" | "float32" | "float64" |
   +            "complex64" | "complex128" | "complex" | "real" | "imag" =>
                    Some(TypeShape::Primitive),
                _ => None,
            }
   @@ -380,6 +383,7 @@ impl<'a> Checker<'a> {
                "int" | "i8" | "i16" | "i32" | "i64" |
                "uint" | "u8" | "u16" | "u32" | "u64" | "uintptr" |
                "float32" | "float64" | "bool" | "byte" | "rune" |
   +            "complex64" | "complex128" => true,
                _ => false,
            }

   ---

   Verification & Regression Coverage

   To prevent future regression of primitive scalar sendability boundaries, add compiler/crates/hy-check/tests/shape_complex_primitive_sendability.rs covering shape derivation and boundary crossing:

   1. Direct Scalar Sendability: Spawning a task with complex64 and complex128 arguments.
   2. Built-in Expression Shapes: Passing results of complex(r, i), real(c), and imag(c) across task boundaries.
   3. Composite Struct Shapes: Defining a struct with nested complex fields (e.g., struct Signal { freq complex128 }) and verifying that TypeShape::Struct derives Sendable without unknown fields.
   4. Channel Boundary Verification: Instantiating chan complex128 and ensuring send (ch <- c) and receive operations resolve properly under rule O4.
2. dukenordj-rgb commented on Nov 7, 2026

   

   dukenordj-rgb

   on Nov 7, 2026

   Contributor

   More actions

   Root Cause Analysis

   Under SPEC §9.2 and GUARANTEES.md (O4), primitive scalar types are strictly value-copied across isolation domains and must evaluate to TypeShape::Primitive during semantic shape analysis.

   In compiler/crates/hy-check/src/shape.rs, complex number primitive identifiers (complex64, complex128) and their shorthand aliases (c64, c128), along with complex numeric built-in calls (complex, real, imag), were missing from pattern matches across three key routines:

   1. Checker::named_shape_depth: Resolved primitive type names to shapes. The absence of complex primitives caused type shape resolution to yield TypeShape::Unknown.
   2. Checker::call_shape: Resolved expression shapes for primitive cast and factory built-in functions. The missing cases evaluated constructor expressions like complex(re, im) to TypeShape::Unknown.
   3. Checker::receiver_type_params: Handled non-generic receiver type filtering. Missing complex types permitted unintended generic parameter checks or misclassifications.

   When sendability.rs checks values against spawn or channel transfer boundaries, unproven or unresolved shapes fall through to the fail-closed defense mechanism (O4.9), triggering HYB-E3005.

   ---

   Patch Solution

   --- a/compiler/crates/hy-check/src/shape.rs
   +++ b/compiler/crates/hy-check/src/shape.rs
   @@ -112,6 +112,7 @@ impl<'a> Checker<'a> {
                "int" | "int8" | "int16" | "int32" | "int64" | "i8" | "i16" | "i32" | "i64" |
                "uint" | "uint8" | "uint16" | "uint32" | "uint64" | "u8" | "u16" | "u32" | "u64" |
                "uintptr" | "float32" | "float64" | "f32" | "f64" | "bool" | "byte" | "rune" |
   +            "complex64" | "complex128" | "c64" | "c128" |
                "string" => Some(TypeShape::Primitive),
                _ => None,
            }
   @@ -185,6 +186,7 @@ impl<'a> Checker<'a> {
                "int" | "int8" | "int16" | "int32" | "int64" | "i8" | "i16" | "i32" | "i64" |
                "uint" | "uint8" | "uint16" | "uint32" | "uint64" | "u8" | "u16" | "u32" | "u64" |
                "uintptr" | "float32" | "float64" | "f32" | "f64" | "bool" | "byte" | "rune" |
   +            "complex64" | "complex128" | "c64" | "c128" | "complex" | "real" | "imag" |
                "string" => Some(TypeShape::Primitive),
                _ => None,
            }
   @@ -240,6 +242,7 @@ impl<'a> Checker<'a> {
                "int" | "int8" | "int16" | "int32" | "int64" | "i8" | "i16" | "i32" | "i64" |
                "uint" | "uint8" | "uint16" | "uint32" | "uint64" | "u8" | "u16" | "u32" | "u64" |
                "uintptr" | "float32" | "float64" | "f32" | "f64" | "bool" | "byte" | "rune" |
   +            "complex64" | "complex128" | "c64" | "c128" |
                "string" => true,
                _ => false,
            }

   ---

   Regression Testing Strategy

   Add an integration test target at compiler/crates/hy-check/tests/shape_complex_primitive_sendability.rs:

   use hy_check::test_utils::check_source;
   
   #[test]
   fn test_complex_primitives_pass_sendability_check() {
       let source = r#"
           package main
   
           struct Signal {
               freq complex128
               c_short c64
           }
   
           fn worker(c complex128, c_alt c64) {}
           fn struct_worker(s Signal) {}
   
           fn main() {
               var c complex128 = complex(1.0, 2.0)
               var c_alt c64 = complex(1.0f32, 2.0f32)
               
               task worker(c, c_alt)
   
               var s Signal = Signal{ freq: c, c_short: c_alt }
               task struct_worker(s)
   
               ch := make(chan complex128, 1)
               ch <- c
   
               r := real(c)
               i := imag(c)
               _ = r
               _ = i
           }
       "#;
   
       let result = check_source(source);
       assert!(
           result.is_ok(),
           "Complex primitives and expressions failed sendability check: {:?}",
           result.err()
       );
   }