before you declare your local socket, could you try calling "QHostInfo testHost = QHostInfo::fromName("google.com");" and see if it still crashes?
Qt Code:
  1. #include <QLocalSocket>
  2. #include <QHostInfo>
  3.  
  4. int main(int argc, char *argv[]){
  5. QHostInfo testHost = QHostInfo::fromName("google.com");
  6. QLocalSocket s;
  7. return 0;
  8. }
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In debug the same assertion fails, crash in release:
Program received signal SIGSEGV, Segmentation fault.
0x6a30dea6 in ZNK7QObject6d_funcEv () from C:\Qt\bin\QtCore4.dll
(gdb) bt
#0 0x6a30dea6 in ZNK7QObject6d_funcEv () from C:\Qt\bin\QtCore4.dll
#1 0x6a2a52bd in ZNK7QObject6threadEv () from C:\Qt\bin\QtCore4.dll
#2 0x6a2b50b4 in ZN21QEventDispatcherWin3221registerEventNotifierEP 17QWinEventN
otifier () from C:\Qt\bin\QtCore4.dll
#3 0x6a2b8d47 in ZN17QWinEventNotifierC2EPvP7QObject ()
from C:\Qt\bin\QtCore4.dll
#4 0x6ff76738 in ZN12QLocalServer21nextPendingConnectionEv ()
from C:\Qt\bin\QtNetwork4.dll
#5 0x6ff7366f in ZN12QLocalSocketC2EP7QObject ()
from C:\Qt\bin\QtNetwork4.dll
#6 0x00401415 in ?? ()
#7 0x00401f9d in ?? ()
#8 0x00401c56 in ?? ()
#9 0x004010db in ?? ()
#10 0x00401158 in ?? ()
#11 0x77621174 in KERNEL32!AcquireSRWLockExclusive ()
from C:\Windows\system32\kernel32.dll
#12 0x77b3b3f5 in ntdll!RtlInsertElementGenericTableAvl ()
from C:\Windows\system32\ntdll.dll
#13 0x77b3b3c8 in ntdll!RtlInsertElementGenericTableAvl ()
from C:\Windows\system32\ntdll.dll
#14 0x00000000 in ?? ()
But this time a warning message appears before crash and failed assertion:
warning: QObject::connect: Cannot connect (null)::destroyed() to QHostInfoLookupManager::waitForThreadPoolDone()