I'm trying to compile cljs's out/ directory manually using GCC but can't figure out the magic incantation. I'm using the all-in-one jar:

java -cp cljs-1.9.946.jar com.google.javascript.jscomp.CommandLineRunner --compilation_level ADVANCED --js goog/'**.jar' --js out/'**.js' --manage_closure_dependencies --closure_entry_point bug.core --js_output_file advanced.js

This gives me errors:

out/cljs/core.js:34828: WARNING - Redeclared variable: self__
var self__ = this;
    ^^^^^^^^^^^^^

out/cljs/core.js:366: ERROR - variable process is undeclared
if((typeof process !== 'undefined') && (!((process.hrtime == null)))){
           ^^^^^^^

out/cljs/core.js:35941: ERROR - variable global is undeclared
return cljs.core.find_ns_obj_STAR_(global,segs);
                                   ^^^^^^

Adding --third_party gives me

out/goog/base.js:526: ERROR - Malformed goog.forwardDeclaration
goog.forwardDeclare('Document');
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

warnings you can ignore

for process you might need an extern, global might just be a bug?

Maybe we need to use goog.global instead

I'm trying to repro nikitonsky's issue by the way https://twitter.com/nikitonsky/status/933315653892820993

@dnolen does the CLJS compiler supply the --third_party flag? Any idea about the goog.forardDeclare issue?

no idea

--third_party thing sounds like something you could reproduce on your own though

and ask on the Closure mailing list if you can’t sort it out - they are responsive

I got stuck on ERROR - variable global is undeclared myself :(

fixed the global issue by going to that line and doing s/global/goog.global/

the process issue can be fixed by adding --closure_entry_point process.env

@pesterhazy feel free to file a ticket for goog.global thing

@dnolen will do

@tonsky when invoking adv compilation manually from the CLI, the compiled output works well

B("bug.core.aaa", function () {
    console.log("aaa start");
    document.querySelector("body").className = "+++aaa+++";

    return console.log("aaa end")
});
B("bug.core.bbb", function () {
    console.log("bbb\u00a0start");
    document.querySelector("body").className = "+++bbb+++";

    return console.log("bbb end")
});
B("bug.core.ccc", function () {
    console.log("ccc start");
    document.querySelector("body").className = "+++ccc+++";

    return console.log("ccc end")
});

must be something about the way cljs calls gcc

I’m very skeptical about such a conclusion still

need to be absolutely positive you’re comparing the same versions of GCC

and probably need to try a couple of other kinds of examples

I'm sure of that

but there could be other enviromental differences

you’re not using Lein or Boot or something else?

test like this should be manual JVM start only

I’ve tried with two GCC versions (one that comes with latest CLJS and october one)

yeah manual java call

k good

the JS output that CLJS produces seems fine. But those lines do disappear after advanced compilation

so it must be GCC and magical set of options

except if CLJS runs its own pass over generated JS, which I doubt

another thing to wonder here is whether we somehow have a bad extern for document.querySelector

those lines would be eliminated only if Closure thought mutating the result of that fn was harmless

let me check if it works with a different function call

better yet just put a fn there that returns #js {}

and try that

I tried that, same result

but then for #js {} it is correct to remove mutations

@tonsky I commented on the ticket. It's a known issue

because that obj would never be used anywhere

@rauh, could you link to the ticket?

oh sorry, I meant something like goog.global

https://dev.clojure.org/jira/browse/CLJS-2410

this is the test script I use : https://github.com/tonsky/closure-elimination-bug/pull/1/files#diff-0b83f9dedf40d7356e5ca147a077acb4

@pesterhazy ah hm, that js/global is for bootstrapped

yep that’s it. Adding --jscomp_off=checkTypes enables elimination mode

the GCC issue doesn’t seem to be very active :(

tried it now, js/document.querySelector gets eliminated, js/document.querySelectorXXX doesn't

@dnolen goog/global is used in the line just below: https://github.com/clojure/clojurescript/blob/master/src/main/cljs/cljs/core.cljs#L11115

is there a reason for this difference?

As far as I know, goog/global works fine in node.js

Damn :closure-warnings {:check-types :warning} produces lots of noise :(

very strange that enabling warnings causes different code to be omitted

Yeah this evals to true for me on nodejs: (identical? js/global goog.global)

@rauh ok good, then perhaps we just need a patch, bootstrap tests should catch any issues

@pesterhazy I think type checking feeds the compilation phases so Closure can do more

@dnolen attached a patch: https://dev.clojure.org/jira/browse/CLJS-2411

thanks!

Yes, script/test-self-parity (which has *target* "nodejs") passes with the patch, making that call 108,914 times.