Description:
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In certain error scenarios, PHP crashes with an access violation instead of reporting the error.

I have so far only identified one specific error that causes the crash, but there may well be others.

Reproduce code:
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$wmiLocator = new COM("WbemScripting.SWbemLocator");
$wmi = $wmiLocator->ConnectServer(".","root/MicrosoftDNS");
$a_rr = $wmi->Get("MicrosoftDNS_AType");
$a_rr->CreateInstanceFromTextRepresentation("","example.com","[*already existent domain name*] IN A 127.0.0.1");

Expected result:
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As indicated in the code, the crash only occurs when attempting to create a domain record that already exists in the DNS server.

The functionally equivalent VBScript code reports a "Generic failure" when the record already exists on the server.

Actual result:
--------------
Access Violation

Stack backtrace:
002cf97c 5a0759f4 OLEAUT32!SysFreeString+0x45
002cf994 5a072278 wbemdisp!SetException+0x1b
002cf9cc 5a07afd9 wbemdisp!CWbemDispatchMgr::Invoke+0x116
*** WARNING: Unable to verify checksum for php5ts.dll
*** ERROR: Symbol file could not be found.  Defaulted to export symbols for php5ts.dll - 
002cf9f8 100e49ec wbemdisp!CSWbemObject::Invoke+0x2f
WARNING: Stack unwind information not available. Following frames may be wrong.
01e791c8 7373656c php5ts!realpath+0x6c1c