gccrs: Add missing bounds checks on the associated impl - #4787
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Before this require_b<T: B> (T) only checked for S<Bad> implement B and it early accepted the impl<T: A> B for S<T> But we need to validate the impl's bound after we bind the arguments being used on the generic impl. So when we do a call-expr/method-call expr we are binding to that impl and we need to validate. When we do that we know that impl T = Bad and we walk the impl generic params T: A apply the subst for Bad: A where its is not implemented and we fail and return. Fixes #4678 gcc/rust/ChangeLog: * typecheck/rust-hir-trait-reference.h: add emit_errors option * typecheck/rust-hir-trait-resolve.cc (AssociatedImplTrait::bind_impl_for_projection): new (AssociatedImplTrait::bind_impl_for_bound): call new validate function * typecheck/rust-type-util.cc (lookup_associated_impl_block): make this more generic * typecheck/rust-tyty-call.cc (validate_call_argument_associated_impl_bounds): new (TypeCheckCallExpr::visit): for each call arg validate and bind (TypeCheckMethodCallExpr::check): likewise gcc/testsuite/ChangeLog: * rust/compile/issue-4678.rs: New test. Signed-off-by: Philip Herron <herron.philip@googlemail.com>
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Before this require_b<T: B> (T) only checked for S implement B and it early accepted the
impl<T: A> B for S
But we need to validate the impl's bound after we bind the arguments being used on the generic impl. So when we do a call-expr/method-call expr we are binding to that impl and we need to validate. When we do that we know that impl T = Bad and we walk the impl generic params T: A apply the subst for Bad: A where its is not implemented and we fail and return.
Fixes #4678
gcc/rust/ChangeLog:
gcc/testsuite/ChangeLog: