On Sun, May 31, 2026 at 2:01 PM 'Stefan Zager' via blink-dev < [email protected]> wrote:
> Hello, > > By default, base::flat_set and base::flat_map cannot be used inside blink. > However, there are about a dozen carve-outs > <https://source.chromium.org/search?q=base::flat_%20f:audit_non_blink_usage.py&sq=&ss=chromium%2Fchromium%2Fsrc>, > and I'm wondering how people would feel about relaxing the restriction more > generally. > > My guess is that there are two primary reasons for the restriction: > > - No support for base:: containers of garbage-collected types > - Mixing redundant/overlapping WTF and base containers could create a big > mess > Yes, those are the major reasons. If we had no clear boundary at all, then it may require regular conversions back and forth within Blink, or major refactoring when a collection that didn't previously need to refer to a GC type starts needing to. The blink/non-blink boundary isn't always ideal for this purpose, but is a pretty good approximation. Cases where a type is just passed through are typically a reasonable case for an exemption, and if done through a type alias or similar it might not even be picked up by audit_non_blink_usage.py at all. Are the other reasons I'm not thinking of? > > How hard would it be to modify the blink GC clang plugin to forbid base:: > containers of garbage-collecte types? > > My motivation here is that there are cases (including one I'm struggling > with right now) where structured data is stored in a base:: container in > cc/, passed to blink/, and then passed back to cc/. In some cases blink > does not use or modify the container; it's just a conduit. In those cases, > we either need to do a pointless round-trip base->WTF->base conversion; or > we need to add entries to audit_non_blink_usage.py which creates a blind > spot for enforcement. > > Thoughts? > > -- > You received this message because you are subscribed to the Google Groups > "blink-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAHOQ7J9Ocib%2BwAetZxg1cx-djJsg6-5zMWyqbmXVfvk1CdGxBw%40mail.gmail.com > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAHOQ7J9Ocib%2BwAetZxg1cx-djJsg6-5zMWyqbmXVfvk1CdGxBw%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "blink-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CACuR13eN-HkPBA6fvTZUmE1ed7PPgEyH4EgggXGEYudEzCiXWQ%40mail.gmail.com.
