pgsql: Fix an oversight in the function-default-arguments patch: after - Mailing list pgsql-committers

Log Message:
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Fix an oversight in the function-default-arguments patch: after adding some
default expressions to a function call, eval_const_expressions must recurse on
those expressions.  Else they don't get simplified, and in particular we fail
to insert additional default arguments if any functions needing defaults are
in there.  Per report from Rushabh Lathia.

Modified Files:
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    pgsql/src/backend/optimizer/util:
        clauses.c (r1.273 -> r1.274)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/util/clauses.c?r1=1.273&r2=1.274)