tree 0b7ba46357f3a528ad5e7ddc92d7c8f0f20988e3
parent 258e47306680682e73d2b873b69fe7e616ae5490
author Robert Findley <rfindley@google.com> 1645648622 -0500
committer Robert Findley <rfindley@google.com> 1645713115 +0000

go/types/typeutil: don't recurse into constraints when hashing tparams

When hashing signature type parameters, we recursed into their
constraints in an attempt to improve the accuracy of the hash
(signatures are considered identical modulo type parameter renaming).

This introduces a mechanism for infinite recursion via recursive
constraints, as reported in golang/go#51314. To fix this, we can hash
just the type parameter index and rely on types.Identical for
de-duplicating map entries.

Fixes golang/go#51314

Change-Id: Ifd7596d978b98293391bbe64f72f1da2b2a5d51c
Reviewed-on: https://go-review.googlesource.com/c/tools/+/387754
Trust: Robert Findley <rfindley@google.com>
Run-TryBot: Robert Findley <rfindley@google.com>
Reviewed-by: Tim King <taking@google.com>
gopls-CI: kokoro <noreply+kokoro@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>