[petsc-users] Compiling PETSc on Windows with Cygwin: errors with `win32fe cl`; okay to use `gcc`, `g++`, `gfortran` as compilers instead of `win32cf cl`?

[Barry Smith]

> On Nov 21, 2015, at 3:05 PM, Brian Merchant <bhmerchant at gmail.com> wrote:
> 
> > [however you can't build petsc with cygwin/gnu compilers - and then
> link in with an application using MS compilers]
> 
> Could you tell me a little more about what you mean here? (sorry, I am a newbie) Is it that if I make an application say in Visual Studio, and attempt to use that application to call PETSc functions compiled with Cygwin, then I will run into trouble?

  Brian,

   If your application is in Visual Studio then you MUST build PETSc with the Microsoft/Intel compilers, you cannot use the cygwin gnu compilers.

> 
> I contacted this group: http://www2.msic.ch/Software
> and got the latest build from them that is supposed to work with Visual Studio; which addresses your MS compilers concern?

  Unfortunately this is the previous release of PETSc so is somewhat out of date. 

  It is very strange that when you tried building you got garbage in the configure.log file. Can you try again (without the \ in compiler name business for any compiler.)
> 
> However, I also want to use petsc4py Python bindings with PETSc, so I shouldn't be in trouble there if I use Cygwin, right? 

   If you want to use petsc4py Python on a  Windows machine then you can try that with the Cygwin Gnu compilers (and the Cygwin python). I don't know if anyone has ever done it so some issues that need fixing may come up but it should be possible.

   It is likely a great deal of work to get the petsc4py Python bindings working with Visual Studio code and the Windows python all together. That would be completely new territory.

  Barry

> 
> Kind regards,
> Brian
> 
> On Sat, Nov 21, 2015 at 12:55 PM, Satish Balay <balay at mcs.anl.gov> wrote:
> Hm - If you can work with cygwin/gnu compilers - then you can build
> petsc with them - and use it.
> 
> [however you can't build petsc with cygwin/gnu compilers - and then
> link in with an application using MS compilers]
> 
> Satish
> 
> On Sat, 21 Nov 2015, Brian Merchant wrote:
> 
> > Hi all,
> >
> > I'd like to try and install PETSc on Windows (even though I have been
> > forewarned that it is better to simply install it on a unix system).
> >
> > Some information about my system:
> > * Windows 10 Pro, 64 bit
> > * latest Cygwin with make, gcc, g++, gfortran installed
> >
> > The PETSc installation instructions suggest that I run the following
> > command:
> >
> >     ./configure --with-cc="win32fe cl"  --with-fc="win32fe ifort"
> > --with-cxx="win32fe\ cl" --download-fblaslapack\
> >
> > However, that results in the following error:
> >
> >     C compiler you provided with -with-cc=win32fe cl does not work.
> >     Cannot compile C with /cygdrive/a/petsc/bin/win32fe/win32fe cl.
> >
> >
> > The answer to this stackexchange question:
> > http://stackoverflow.com/questions/30229620/petsc-build-error-c-compiler-does-not-work
> >
> > recommends the following command instead (with escaped whitespace):
> >
> >     ./configure --with-cc="win32fe\ cl"  --with-fc="win32fe\ ifort"
> > --with-cxx="win32fe\ cl" --download-fblaslapack
> >
> > Running that command results in the following error (note no second line in
> > error):
> >
> >     C compiler you provided with -with-cc=win32fe\ cl does not work.
> >
> > In both cases, the configure.log output only contains (I do not use Chinese
> > characters, these were in the file):
> >
> > > 㰡祳汭湩㹫arch-mswin-c-debug/lib/petsc/conf/configure.log
> >
> > What should I do? Also, do `gcc`/`g++` compiled programs not work on
> > Windows? I ask because if I simply run the suggested command in the "Quick
> > Installation" guide, using `gcc` and `g++`; then I don't get compilation
> > errors. Would it be okay to simply use those compilers then?
> >
> > Kind regards,
> > Brian
> >
>