Link to patch publishing PR
diff --git a/Cargo.toml b/Cargo.toml
index ed1840b..1529c86 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -44,4 +44,6 @@
 #
 # When publishing proc-macro2, Cargo will forbid publishing with a patch
 # section. You need to delete this section and then publish with --allow-dirty.
+# A PR https://github.com/rust-lang/cargo/pull/6535 proposes to make it no
+# longer an error to publish with a patch section.
 proc-macro2 = { path = "." }