Still disabled.

That function checks for buffer->successful already.  No need
to check at call site.

Untested.

Started by reverting https://github.com/harfbuzz/harfbuzz/commit/1f1c85a5

Just a starting point, if we agree even mort can come back.

Show up with gcc -O0.

There's a few more but those are functions that need to be filled in.

Maybe this is a lost battle...

https://github.com/harfbuzz/harfbuzz/issues/1302

Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=11060

Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=11034

Ugly as hell, and don't even understand why some bits are needed.
But the logic is sound.

It has unbounded size...

Fixes https://oss-fuzz.com/v2/testcase-detail/5718889451749376

Unfortunately our static asserts (DEFINE_SIZE_STATIC) don't actually
fail when used in templates, thanks to SFINAE.  Le sighs.

Probably fixes https://oss-fuzz.com/v2/testcase-detail/5740171484463104

Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=10897

Works beautifully!  Test coming.

Tested with Kannada MN:

$ HB_OPTIONS=aat ./hb-shape Kannada\ MN.ttc -u 0CCD,0C95,0CD6
[kn_ka.vattu=0+230|kn_ai_length_mark=1@326,0+607]

For 329f2401

max_ops is signed.

Since we consume it legitimately during shaping.

Not hooked up to be called yet.

If buffer was enlarged, info was being outdated.

Fixes https://github.com/harfbuzz/harfbuzz/issues/1225

Was getting stuck not making progress somehow.

...like UnsizedArrayOf<>.

This fixes a class of crasher bugs, mostly with color and AAT tables.  We
cannot use nullable offsets to varsized data that does not declare min_size,
because it's nost safe to use our fixed-size null pool for types that have
their size external.  So, use non_null'able offsets for these.

A further enhancement would be to make use of min_size in Null<> itself.
Will try that after.

Not sure how I didn't add before...