There is a huge piece of code with huge comments in sql_yacc.yy:
responsible to display a warning when a user shadows a built-in function with a stored function.
The same warning will be needed for package routines (
We'll move this piece of code to sql_lex.cc into a new function is_native_function_with_warn().
This change was originally a part of
MDEV-11952, but it was decided to commit it as a standalone change.