serde 1.0.172 and up rely on opaque non-reproducible binary blobs to
function, explicitly not providing a library-level opt-out.
This is problematic for two reasons:
- directly, unauditable binary blobs are a security issue.
- indirectly, it becomes much harder to predict future behaviors of the
crate.
As such, I am willing to go on a limb here and forbid building
rust-analyzer with those versions of serde. Normally, my philosophy is
to defer the choice to the end user, but it's also a design constraint
of rust-analyzer that we don't run random binaries downloaded from the
internet without explicit user's concent.
Concretely, this upper-bounds serde for both rust-analyzer workspace, as
well as the lsp-server lib.
See https://github.com/serde-rs/serde/issues/2538 for wider context.
