Double compilation during bootstrap

[nasser]

The following namespaces are being double compiled during bootstrapping.

• clojure.clr.io
• clojure.core.protocols
• clojure.edn
• clojure.instant
• clojure.main
• clojure.set
• clojure.string
• clojure.uuid
• clojure.walk

[skydread1]

Explanation

The double compilation occurs when

• the ns was required by another ns (and so got compiled automatically)
• (compile 'required-ns) was called after (compile 'requiring-ns)

Example

clojure.core.protocols requires clojure.set

so if the compilation order is

(compile 'clojure.core.protocols)
(compile 'clojure.set)

clojure.set will be compiled twice (once because required in clojure.core.protocols and once on its own.

but if the compilation order is

(compile 'clojure.set)
(compile 'clojure.core.protocols)

clojure.set will be compiled once.

That's my understanding.

[nasser]

if i recall the expected semantics, compile should see that clojure.set was already compiled and not compile it a second time. does it double compile on the JVM?

[nasser]

Fixed by 8d52baab28c7b78c2d16dc4418bae1c59059edb8