playground: Update for Go 1.9.

[dmitshur]

This should be done with GopherJS version 1.9-1.

[dmitshur]

I'm investigating this right now.

Everything seems to work okay, except that something causes unsafe package to get loaded, and that fails, because it's not one of the installed packages:

https://github.com/gopherjs/gopherjs.github.io/blob/b7ffcc8bb375a70cc85b414ec55636f102fe68c8/playground/update.sh#L135-L138

I tried adding it to that list, and that fixes the problem:

diff --git a/playground/update.sh b/playground/update.sh
index 5d62c70..578a5fa 100755
--- a/playground/update.sh
+++ b/playground/update.sh
@@ -134,7 +135,8 @@ gopherjs install -m \
          time \
          unicode \
          unicode/utf16 \
-         unicode/utf8
+         unicode/utf8 \
+         unsafe

 cp -a "$GOROOT"/pkg/*_js_min/* pkg/
 cp -a "$GOROOT"/pkg/*_amd64_js_min/* pkg/

However, I want to look around first to see if there's a better fix, and whether this is indicative of a problem somewhere in GopherJS 1.9-1.

[dmitshur]

The "unsafe" package is special-cased here:

https://github.com/gopherjs/gopherjs/blob/95deb33d587c9f6e24b494ea9bdf9648c48f9a60/compiler/package.go#L105-L107

I want to see what changed related to that causing it to be included as part of a build, where previously it wasn't.

[dmitshur]

This is the generated code for the unsafe package:

$packages["unsafe"] = (function() {
    var $pkg = {}, $init;
    $init = function() {
        $pkg.$init = function() {};
        /* */ var $f, $c = false, $s = 0, $r; if (this !== undefined && this.$blk !== undefined) { $f = this; $c = true; $s = $f.$s; $r = $f.$r; } s: while (true) { switch ($s) { case 0:
        /* */ } return; } if ($f === undefined) { $f = { $blk: $init }; } $f.$s = $s; $f.$r = $r; return $f;
    };
    $pkg.$init = $init;
    return $pkg;
})();

It's basically empty (aside from bookkeeping related to goroutines and blocking calls). It contains an empty init function, and that's the only thing that gets called by other packages.

[dmitshur]

Figured it out. It's due to an API change in go/types package (https://github.com/golang/go/issues/21622).

"go/types".Package.Imports used to exclude package unsafe in Go 1.8, but no longer does in 1.9.

Compare https://gotools.org/go/types?rev=go1.8.3#package.go-L54-L55 vs https://gotools.org/go/types?rev=go1.9#package.go-L50-L51.

[dmitshur]

I might need to make additional changes, so I've undone the deploy of 8bcc3f3a576ba326bbd26a1d27f5de696b8cf9dd for now.