Point standard library links to stable

Author: dtolnay

Cargo.toml

@@ -67,7 +67,14 @@ required-features = ["full", "parsing"]
 [package.metadata.docs.rs]
 all-features = true
 targets = ["x86_64-unknown-linux-gnu"]
-rustdoc-args = ["--generate-link-to-definition", "--extend-css=src/gen/token.css"]
+rustdoc-args = [
+    "--generate-link-to-definition",
+    "--extend-css=src/gen/token.css",
+    "--extern-html-root-url=core=https://doc.rust-lang.org",
+    "--extern-html-root-url=alloc=https://doc.rust-lang.org",
+    "--extern-html-root-url=std=https://doc.rust-lang.org",
+    "--extern-html-root-url=proc_macro=https://doc.rust-lang.org",
+]
 
 [package.metadata.playground]
 features = ["full", "visit", "visit-mut", "fold", "extra-traits"]

json/Cargo.toml

@@ -25,6 +25,11 @@ serde_json = "1"
 
 [package.metadata.docs.rs]
 targets = ["x86_64-unknown-linux-gnu"]
-rustdoc-args = ["--generate-link-to-definition"]
+rustdoc-args = [
+    "--generate-link-to-definition",
+    "--extern-html-root-url=core=https://doc.rust-lang.org",
+    "--extern-html-root-url=alloc=https://doc.rust-lang.org",
+    "--extern-html-root-url=std=https://doc.rust-lang.org",
+]
 
 [workspace]