https://github.com/kkos/oniguruma/commit/778a43dd56925ed58bbe26e3a7bb8202d72c3f3f

It differs from the Oniguruma patch in that it dosen't use `onigenc_get_prev_char_head()`
because this function's signature has been changed by Oniguruma and the change is not ported
in Onigmo for now. This patch respects the current Onigmo implementation.

Co-Authored-By: K.Kosako <kkos@users.noreply.github.com>

https://github.com/kkos/oniguruma/commit/bfc36d3d8139b8be4d3df630d625c58687b0c7d4

Co-Authored-By: K.Kosako <kkos@users.noreply.github.com>

https://github.com/kkos/oniguruma/commit/db64ef3189f54917a5008a02bdb000adc514a90a

Co-Authored-By: K.Kosako <kkos@users.noreply.github.com>

	[Bug #20239] Fix overflow at down-casting

	[Bug #20305] Fix matching against an incomplete character

	When matching against an incomplete character, some `enclen` calls are
	expected not to exceed the limit, and some are expected to return the
	required length and then the results are checked if it exceeds.

	Fix Use-After-Free issue for Regexp

	Co-authored-by: Isaac Peka <7493006+isaac-peka@users.noreply.github.com>
	---
	 regexec.c | 2 +-
	 1 file changed, 1 insertion(+), 1 deletion(-)

	Fix handling of reg->dmin in Regex matching

	---
	 regexec.c | 10 ++++++++++
	 1 file changed, 10 insertions(+)

	Fix `PLATFORM_GET_INC`

	On platforms where unaligned word access is not allowed, and if
	`sizeof(val)` and `sizeof(type)` differ:

	- `val` > `type`, `val` will be a garbage.
	- `val` < `type`, outside `val` will be clobbered.
	---
	 regexec.c | 2 +-
	 regint.h  | 9 ++++++++-
	 2 files changed, 9 insertions(+), 2 deletions(-)