transpile: Fix translation failures exposed by SQLite - #2001
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Translation units without declarations have no AST nodes to register their main file. Exporting comments then introduces a file ID absent from the file table, causing include-path lookup to panic. Register the main file before serializing the table so comments always refer to an exported file.
…nters Exposed-provenance constructors require Sized pointees, but forward declarations become unsized extern types. Construct a byte pointer first, then cast to the opaque pointer type while preserving its constness. This allows integer sentinel values and runtime addresses to initialize opaque pointers in both supported Rust editions.
… va_arg An enclosing cast can prevent Rust from inferring the destination of the transmute used for nullable function pointers. Pass the converted C type explicitly so va_arg results can be assigned through function pointer typedefs and struct fields.
Rust atomic intrinsics reject Option<fn>, the representation of nullable C function pointers. Convert atomic operands to raw pointers and convert results back to their function pointer type. Apply this to loads, stores, exchanges, and compare-exchanges, including the expected value written back after a failed comparison. Null callbacks retain their null representation.
Default initialization does not handle CTypeKind::Atomic, so local _Atomic declarations fail to translate even when they have an explicit initializer. Delegate to the underlying value type to produce the initializer for the atomic storage.
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| } | ||
| #[unsafe(no_mangle)] | ||
| pub unsafe extern "C" fn sentinel() -> *mut Opaque { | ||
| return ::core::ptr::with_exposed_provenance_mut::<u8>(8 as ::core::ffi::c_int as usize) |
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If there isn't a matching call to expose_provenance, this is undefined behavior.
| .ast_context | ||
| .is_forward_declared_type(pointee_type_id.ctype); | ||
| let pointee_type_rs = if is_opaque { | ||
| mk().path_ty(vec!["u8"]) |
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I'm not sure yet if this should be u8 or c_void.
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We use c_void in other places, so yeah we should keep it consistent.
| transmute_expr(mk().infer_ty(), mk().infer_ty(), val) | ||
| VaArgCastKind::Transmute(ty) => { | ||
| // An enclosing cast or field access may prevent | ||
| // inference of the transmute's destination type. |
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Could either this comment or the current commit message provide an example of the generated code?
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| .transpose()?; | ||
| let weak = weak_id.and_then(|x| self.convert_constant_bool(x)); | ||
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| // Rust represents nullable C function pointers as Option<fn>, which |
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This only covers the AST atomics, but not any of the __sync_* or __atomic_* builtins. You could refactor this to cover everything.
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Fix five translation failures exposed by SQLite's individual source files:
va_arg. Enclosing casts can prevent Rust from inferring it.Option<fn>representation of nullable C callbacks._Atomicstorage through its underlying value type. Default initialization otherwise fails for local atomic declarations, including explicitly initialized ones.