backend: Fix incorrect impl block selection#4660
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During vtable generation in `compute_address_for_trait_item`, the compiler was picking the first `impl` block that satisfied the trait predicate, without verifying if the `impl` block actually belonged to the target receiver type. This caused dynamic dispatch to call the wrong methods when multiple types implemented the same trait in the same scope. This patch adds a comparison between the impl block's resolved type and the `receiver` type to ensure we compute the address of the correct associated function. gcc/rust/ChangeLog: * backend/rust-compile.cc (HIRCompileBase::compute_address_for_trait_item): Ensure the impl block type matches the receiver type. gcc/testsuite/ChangeLog: * rust/execute/trait-multi-impl.rs: New test. * rust/execute/trait-multi-impl-generic.rs: New test. * rust/execute/trait-multi-impl-generic2.rs: New test. Signed-off-by: Enes Cevik <enes@nsvke.com>
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During vtable generation in
compute_address_for_trait_item, the compiler was picking the firstimplblock that satisfied the trait predicate, without verifying if theimplblock actually belonged to the target receiver type. This caused dynamic dispatch to call the wrong methods when multiple types implemented the same trait in the same scope.This patch adds a comparison between the impl block's resolved type and the
receivertype to ensure we compute the address of the correct associated function.Fixes #4600
gcc/rust/ChangeLog:
gcc/testsuite/ChangeLog: