[CBRD-23600] Unexpected rounding up a numeric value when the case expressions are used recursively

[hgryoo]

http://jira.cubrid.org/browse/CBRD-23600

When the CASE expressions are used recursively and values specified in the THEN clause are numeric and integer types order repeatedly, one of the numeric values is rounded up unexpectedly.

this bug causes because the arg1 pointer variable for PT_NODE is incorrectly re-used at the part of checking the next case clause. please see the changes in this PR. To make a common data type of expression, pt_upd_domain_info () is invoked with the possibly wrong assigned arg1. As a consequence, the data type is going to be updated incorrect precision and scale.

It fixes to keep the arg1 from being re-used incorrectly.

[beyondykk9]

I think you found a good debugging point. This error is commonly found when the function routine is too long.

[shparkcubrid]

It would be better if there was an explanation of why the reuse of arg1 was not the intended reuse.