oup the size increases by 16 bytes.
</P>
<P>
Until release 10.41, an initial 20KiB frames vector was allocated on the system
stack, but this still caused some issues for multi-thread applications where
each thread has a very small stack. From release 10.41 backtracking memory
frames are always held in heap memory. An initial heap allocation is obtained
the first time any match data block is passed to <b>pcre2_match()</b>. This is
remembered with the match data block and re-used if that block is used for
ano