Description:
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snmp2_walk() is occasionally (but consistently) returning the wrong value for certain OIDs on certain devices. snmp2_real_walk(), snmp2_get, and other external utilities all report the correct value.

Reproduce code:
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        $test1 = snmp2_get($dev, $comm, "ifHCInOctets.163");
        $test2 = snmp2_real_walk($dev, $comm, "ifHCInOctets");
        $test3 = snmp2_walk($dev, $comm, "ifHCInOctets");
        $proof = snmp2_walk($dev, $comm, "ifIndex");

        print "SNMP2_GET test: $test1\n";
        print "SNMP2_REAL_WALK test: {$test2['.1.3.6.1.2.1.31.1.1.1.6.163']}\n";
        print "SNMP2_WALK test: {$test3[83]}\n";
        print "Proof that I'm looking at the right ifindex: {$proof[83]}\n";



Expected result:
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I expect snmp2_walk() to return correct results. :)

Actual result:
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SNMP2_GET test: 1280817516439889
SNMP2_REAL_WALK test: 1280817516439889
SNMP2_WALK test: 3545696399506456
Proof that I'm looking at the right ifindex: 163