1555990 - fix theoretical xptcodegen issue with nested array types

Status: RESOLVED FIXED

(Core :: XPCOM, defect)

Comment 1

[Nathan Froyd [:froydnj]]

Attachment: Bug 1555990 - fix theoretical xptcodegen issue with nested array types; r=nika

When we're lowering extra types (e.g. array element types) and we find
that we haven't already lowered the type, we say that the new type is
going to live at the end of the types array. But we don't append a
new type (i.e. filling in the entry) until after we call lower_type,
which means that some other call to lower_extra_type might find
that its new type will live at the same position we "allocated" higher
up on the stack.

We don't appear to run into this issue, as the only nested array types
are things like Array<Array<uint8>>, and uint8 is guaranteed to
already have been lowered. But if people start doing more complicated
things, we're bound to run into this sooner or later.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/db5ce1365927
fix theoretical xptcodegen issue with nested array types; r=nika

Comment 3

[Arthur Iakab [arthur_iakab]]

https://hg.mozilla.org/mozilla-central/rev/db5ce1365927