Description:
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If json_last_error() returns an error state, calling getResponse() causes a segfault.

Clearing json_last_error() by performing a successful json_decode or json_encode prevents the segfault.

I'm on solr 2.4.0 and PHP Version 7.0.15-0ubuntu0.16.04.4, the latest package from Ubuntu 16 LTS.

Test script:
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<?php
json_decode("", true);

// uncommnt below to prevent segfault
// json_decode("[1]");

$client = new SolrClient(array('hostname' => 'myhost', 'port' => 'myport', 'path' => 'mypath', 'wt' => 'json'));

$query = new SolrQuery();

$query->setQuery('*:*');

$response = $client->query($query);

// results in segfault
$results = $response->getResponse();

Expected result:
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segfault