BUG #6692: Potential Bug in equalfuncs.c

The following bug has been logged on the website:

Bug reference:      6692
Logged by:          Ken Cheung
Email address:      msrbugzilla@gmail.com
PostgreSQL version: 9.1.3
Operating system:   Linux
Description:=20=20=20=20=20=20=20=20

I observed a code clone in the following files. The function
"COMPARE_LOCATION_FIELD" is called in some functions and missed in other
functions. I wonder if this is a bug. Hope it helps.

function : _equalA_ArrayExpr @ (file:
"postgresql-9.1.3/src/backend/nodes/equalfuncs.c", line: 2118)~2121
    COMPARE_NODE_FIELD(elements);
    COMPARE_LOCATION_FIELD(location);

    return true;

function : _equalAlternativeSubPlan @ (file:
"postgresql-9.1.3/src/backend/nodes/equalfuncs.c", line: 415)~417
    COMPARE_NODE_FIELD(subplans);

    return true;

function : _equalColumnRef @ (file:
"postgresql-9.1.3/src/backend/nodes/equalfuncs.c", line: 2051)~2054
    COMPARE_NODE_FIELD(fields);
    COMPARE_LOCATION_FIELD(location);

    return true;

function : _equalDoStmt @ (file:
"postgresql-9.1.3/src/backend/nodes/equalfuncs.c", line: 1306)~1308
    COMPARE_NODE_FIELD(args);

    return true;