In particular, we implicitly required that the caller initializes the
returned instances themselves (solved by making
UniformBumpAllocator::allocate call the constructor), and BumpAllocator
itself cannot handle classes that are not trivially deconstructible
(solved by deleting the method).
Co-authored-by: Ali Mohammad Pur <ali.mpfard@gmail.com>
This fixes two bugs:
1. `end_offset` was missing the alignment that might have been
introduced while computing `base_ptr`.
2. Ignoring point 1, `end_offset` computed the offset of the first byte
that is outside the current chunk. However, this might be in the
middle of a (hypothetical) object! The loop treats `end_offset` as if
it points to the first byte beyond the last (valid) object. So if the
last few bytes of the chunk are unused, the loop iterates once too
often.
Found by OSS Fuzz, long-standing issue (since 2021-07-31)
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=38733
(This probably also resolves some other issues that go through
RegexMatcher.)
See also: 0f1425c895
When compiling this code with Clang, both branches of the ternary
operator get evaluated at compile-time, triggering a warning about a
narrowing implicit conversion. We can use `explode_byte` instead.
