False positive in G-9501 when using assignment in variable of declare section

[PhilippSalvisberg]

The following code detects a violation of "G-9501: Never use parameter in string expression of dynamic SQL. Use asserted local variable instead.":

create or replace procedure exec_sql(in_sql in varchar2) is
   l_sql          varchar2(1000 char) := in_sql;
   l_sql_asserted varchar2(1000 char);
begin
   l_sql_asserted := sys.dbms_assert.noop(l_sql);
   execute immediate l_sql_asserted;
end exec_sql;
/

It works when rewritten this way:

create or replace procedure exec_sql(in_sql in varchar2) is
   l_sql          varchar2(1000 char) := sys.dbms_assert.noop(in_sql);
begin
   execute immediate l_sql;
end exec_sql;
/

However, this detects a "G-2160: Avoid initializing variables using functions in the declaration section.". Which is correct.

The assignment in the declare section honors guideline "G-8310: Always validate input parameter size by assigning the parameter to a size limited variable in the declaration section of program unit."

This issue is related to #55.