Logic error (PVS-Studio).

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/branches/B2_1_Release@59169 65644016-39b1-43b1-bf79-96bc8fe82c15
Warning (PVS-Studio).

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/branches/B2_1_Release@59170 65644016-39b1-43b1-bf79-96bc8fe82c15
nightly update

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/branches/B2_1_Release@59175 65644016-39b1-43b1-bf79-96bc8fe82c15