Issue #973436 by catch, joseph.olstad, beejeebus, karschsp, pillarsdotnet,...

Issue #973436 by catch, joseph.olstad, beejeebus, karschsp, pillarsdotnet, mcdruid, DamienMcKenna, carlos8f, sun, dsobon, kentr, Damien Tournoud, pounard, Fabianx, xjm, fgm, Steven Jones, David_Rothstein, donquixote, amateescu, MustangGB, Lars Toomre, basicmagic.net, Jeremy, DanPir, nnewton, yonailo, Peter Bowey, RobLoach, gdaw, dsutter, joel_osc, nareshp, izmeez, joelpittet, torgosPizza, crea, tim.plunkett, YesCT, stefan.r, rwohleb: Overzealous locking in variable_initialize()