Andrey Turkin has stated at http://bugs.winehq.org/show_bug.cgi?id=24018 that this is really a Cygwin bug. I frankly don't understand the technical details but his current test (an infinite loop with Cygwin fork calls) may need some beefing up to convince the Cygwin developers they have introduced a regression.
The reason why I mention a Cygwin regression is the winetricks script mentions bug 24018 and works around it by downloading an old version of the Cygwin installer. I haven't tried that myself yet, but if that workaround still works, then this is evidence that the issue is a Cygwin regression which is an important consideration when reporting this issue to the Cygwin developers.
Andrey Turkin was asked at http://bugs.winehq.org/show_bug.cgi?id=24018 to report the issue to Cygwin, but my search of the Cygwin mailing list archive didn't find any post from him and only found one extremely casual (an aside to a completely different thread) mention (http://sourceware.org/ml/cygwin/2013-06/msg00471.html) from a different wine developer of bug 24018 with no response to that mention.
I currently have no experience with Cygwin and my only real interest in Cygwin on Wine is it theoretically provides an alternative build platform to my present successful work with the combination of MinGW, MSYS, and Wine as a Windows build platform. But I haven't even been able to get started with Cygwin on Wine because of this showstopping bug. Therefore, I am mentioning the situation here in the hope that some wine developer on this list with some knowledge of Cygwin will take the responsibility of making a proper bug report to the Cygwin mailing list (which according to http://cygwin.com/problems.html is the correct place to report Cygwin bugs) including the evidence that the issue is a Cygwin regression (assuming investigation of older Cygwin versions with Turkin's test supports that conclusion).
Alan __________________________ Alan W. Irwin
Astronomical research affiliation with Department of Physics and Astronomy, University of Victoria (astrowww.phys.uvic.ca).
Programming affiliations with the FreeEOS equation-of-state implementation for stellar interiors (freeeos.sf.net); the Time Ephemerides project (timeephem.sf.net); PLplot scientific plotting software package (plplot.sf.net); the libLASi project (unifont.org/lasi); the Loads of Linux Links project (loll.sf.net); and the Linux Brochure Project (lbproject.sf.net). __________________________
Linux-powered Science __________________________