patch 8.2.3883: crash when switching to other regexp engine fails Commit: https://github.com/vim/vim/commit/5937c7505f444dd896f336fa0119a93a55ebe9a2 Author: Bram Moolenaar <Bram@vim.org> Date: Fri Dec 24 16:46:14 2021 +0000 patch 8.2.3883: crash when switching to other regexp engine fails Problem: Crash when switching to other regexp engine fails. Solution: Check for regprog being NULL.

# Clang 12 (or Apple clang 13) and later makes a warning '-Wcompound-token-split-by-macro' enable by default.
/^PERL_CFLAGS[[:blank:]]*=/s/$/ -Wno-error=compound-token-split-by-macro/
/^RUBY_CFLAGS[[:blank:]]*=/s/$/ -Wno-error=compound-token-split-by-macro/