> Starting with release 10.38 PCRE2 drops default support for using \K in
> lookaround patterns as described in [1]. Unfortunately, scripts/tags.sh
> relies on such functionality to collect all_compiled_soures() leading to
> the following error:
>
> $ make COMPILED_SOURCE=1 tags
> GEN tags
> grep: \K is not allowed in lookarounds (but see PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK)
>
> The usage of \K for this pattern was introduced in commit 4f491bb6ea2a
> ("scripts/tags.sh: collect compiled source precisely") which speeds up
> the generation of tags significantly.
>
> In order to fix this issue without compromising the performance we can
> switch over to an equivalent sed expression. The same matching pattern
> is preserved here except \K is replaced with a backreference \1.
Just got a working grep without \K, seems that it is three times more
efficient than sed in my test, is it necessary to update?
grep -Poh '(?<=^ )\S+|(?<== )\S+[^\\](?=$)' {} \+ |
--
Jialu
