Merging upstream version 1.69.0+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 17 insertions, 0 deletions

diff --git a/src/doc/rustc-dev-guide/src/solve/the-solver.md b/src/doc/rustc-dev-guide/src/solve/the-solver.md
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+# The solver
+
+Also consider reading the documentation for [the recursive solver in chalk][chalk]
+as it is very similar to this implementation and also talks about limitations of this
+approach.
+
+[chalk]: https://rust-lang.github.io/chalk/book/recursive.html
+
+The basic structure of the solver is a pure function
+`fn evaluate_goal(goal: Goal<'tcx>) -> Response`.
+While the actual solver is not fully pure to deal with overflow and cycles, we are
+going to defer that for now.
+
+To deal with inference variables and to improve caching, we use
+[canonicalization](./canonicalization.md).
+
+TODO: write the remaining code for this as well.