150453 2015-10-22 10:56:46 -0700 We don't properly optimize TDZ checks when we declare a let variable without an initializer 2016-03-29 15:11:27 -0700 1 1 1 Unclassified WebKit JavaScriptCore WebKit Nightly Build Unspecified Unspecified RESOLVED FIXED P2 Normal --- 1 saam saam benjamin commit-queue fpizlo ggaren gskachkov keith_miller mark.lam msaboff oliver sukolsak ysuzuki oldest_to_newest 1135735 0 saam 2015-10-22 10:56:46 -0700 i.e: ``` let v; return v; ``` has a TDZ check on the return value. But, if we do: ``` let v = 20; return v; ``` we optimize out the TDZ check. 1178295 1 saam 2016-03-26 11:53:24 -0700 This is probably a one line patch. I'm going to do it soon 1178757 2 275121 saam 2016-03-29 12:45:57 -0700 Created attachment 275121 Patch 1178764 3 275121 mark.lam 2016-03-29 12:54:08 -0700 Comment on attachment 275121 Patch r=me 1178826 4 275121 commit-queue 2016-03-29 15:11:23 -0700 Comment on attachment 275121 Patch Clearing flags on attachment: 275121 Committed r198803: <http://trac.webkit.org/changeset/198803> 1178827 5 commit-queue 2016-03-29 15:11:27 -0700 All reviewed patches have been landed. Closing bug. 275121 2016-03-29 12:45:57 -0700 2016-03-29 15:11:23 -0700 Patch a-backup.diff text/plain 1393 saam SW5kZXg6IFNvdXJjZS9KYXZhU2NyaXB0Q29yZS9DaGFuZ2VMb2cKPT09PT09PT09PT09PT09PT09 PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PQotLS0gU291 cmNlL0phdmFTY3JpcHRDb3JlL0NoYW5nZUxvZwkocmV2aXNpb24gMTk4Nzg3KQorKysgU291cmNl L0phdmFTY3JpcHRDb3JlL0NoYW5nZUxvZwkod29ya2luZyBjb3B5KQpAQCAtMSwzICsxLDEzIEBA CisyMDE2LTAzLTI5ICBTYWFtIGJhcmF0aSAgPHNiYXJhdGlAYXBwbGUuY29tPgorCisgICAgICAg IFdlIGRvbid0IHByb3Blcmx5IG9wdGltaXplIFREWiBjaGVja3Mgd2hlbiB3ZSBkZWNsYXJlIGEg bGV0IHZhcmlhYmxlIHdpdGhvdXQgYW4gaW5pdGlhbGl6ZXIKKyAgICAgICAgaHR0cHM6Ly9idWdz LndlYmtpdC5vcmcvc2hvd19idWcuY2dpP2lkPTE1MDQ1MworCisgICAgICAgIFJldmlld2VkIGJ5 IE5PQk9EWSAoT09QUyEpLgorCisgICAgICAgICogYnl0ZWNvbXBpbGVyL05vZGVzQ29kZWdlbi5j cHA6CisgICAgICAgIChKU0M6OkVtcHR5TGV0RXhwcmVzc2lvbjo6ZW1pdEJ5dGVjb2RlKToKKwog MjAxNi0wMy0yOSAgSm9zZXBoIFBlY29yYXJvICA8cGVjb3Jhcm9AYXBwbGUuY29tPgogCiAgICAg ICAgIFdlYiBJbnNwZWN0b3I6IFdlIHNob3VsZCBoYXZlIGEgd2F5IHRvIGNhcHR1cmUgaGVhcCBz bmFwc2hvdHMgcHJvZ3JhbWF0aWNhbGx5LgpJbmRleDogU291cmNlL0phdmFTY3JpcHRDb3JlL2J5 dGVjb21waWxlci9Ob2Rlc0NvZGVnZW4uY3BwCj09PT09PT09PT09PT09PT09PT09PT09PT09PT09 PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT09PT0KLS0tIFNvdXJjZS9KYXZhU2Ny aXB0Q29yZS9ieXRlY29tcGlsZXIvTm9kZXNDb2RlZ2VuLmNwcAkocmV2aXNpb24gMTk4Nzc0KQor KysgU291cmNlL0phdmFTY3JpcHRDb3JlL2J5dGVjb21waWxlci9Ob2Rlc0NvZGVnZW4uY3BwCSh3 b3JraW5nIGNvcHkpCkBAIC0yMTUxLDYgKzIxNTEsOCBAQCBSZWdpc3RlcklEKiBFbXB0eUxldEV4 cHJlc3Npb246OmVtaXRCeXRlCiAgICAgICAgIGdlbmVyYXRvci5lbWl0UHJvZmlsZVR5cGUodmFs dWUuZ2V0KCksIHZhciwgcG9zaXRpb24oKSwgSlNUZXh0UG9zaXRpb24oLTEsIHBvc2l0aW9uKCku b2Zmc2V0ICsgbV9pZGVudC5sZW5ndGgoKSwgLTEpKTsgCiAgICAgfQogCisgICAgZ2VuZXJhdG9y LmxpZnRURFpDaGVja0lmUG9zc2libGUodmFyKTsKKwogICAgIC8vIEl0J3Mgc2FmZSB0byByZXR1 cm4gbnVsbCBoZXJlIGJlY2F1c2UgdGhpcyBub2RlIHdpbGwgYWx3YXlzIGJlIGEgY2hpbGQgbm9k ZSBvZiBEZWNsYXJhdGlvblN0YXRlbWVudCB3aGljaCBpZ25vcmVzIG91ciByZXR1cm4gdmFsdWUu CiAgICAgcmV0dXJuIG51bGxwdHI7CiB9Cg==