RE: Regression in Cygwin 3.2.0

[David Allsopp <David.Allsopp@cl.cam.ac.uk>]

Takashi Yano wrote:
> On Fri, 16 Apr 2021 11:17:50 +0100
> David Allsopp wrote:
> > I'm unable to build OCaml using the mingw-w64 compilers with Cygwin
> 3.2.0.
> > Windows 10.0.19042.928 (and tried on three different machines so far)
> >
> > Repro:
> >
> >  - Fresh Cygwin64 installation with make, libiconv,
> > mingw64-x86_64-gcc-core and git added; fire up mintty
> >  - git clone --depth 1 --recursive https://github.com/ocaml/ocaml
> >  - cd ocaml && ./configure --host=x86_64-w64-mingw32 && make -j8
> > flexdll && make -j8 world.opt
> >
> > This is consistently hanging with Cygwin 3.2.0 and seems possibly to
> > have something to do with linking (the creation of
> > runtime/ocamlrun.exe and stdlib/camlheader, which is also an
> > executable, seem to be part of the problem).
> >
> > It can be immediately fixed by downgrading to Cygwin 3.1.7, cleaning
> > the tree and repeating the build.
> >
> > I'm of course very happy to try to reduce this to a smaller repro
> > case, but is there an obvious culprit in Cygwin 3.2.0 to check before I
> do?
> 
> Thanks for the report. I looked into this problem and found that the
> caused is the combination of some race issues for non-cygwin processes in
> pty and console code.
> 
> I will submit the patches fixing this issue.

Fantastic, thanks - I'll keep an eye on cygwin-patches and test.


David