[petsc-dev] Compiling C code with C compiler

[Barry Smith]

On Apr 5, 2011, at 10:02 AM, Jed Brown wrote:

> On Tue, Apr 5, 2011 at 14:36, Barry Smith <bsmith at mcs.anl.gov> wrote:
> If it is as simple as you say then I am fine with adding support BUT it will require "yet another flag"

  If you don't have a flag to turn off using the C or C++ compiler on the "C" code then you are forcing the user into the model of C for C code and C++ for C++ code which we have never supported in 15 plus years. This is a new feature and has to have a way of turning it off. 

   Barry

If you make the C for C code feature the default that might not be the end of the world but you cannot make it be the only possibility.

> 
> I'm not sure about this. What does PETSc need to do at compile time to expose the C++ interface? Isn't all the genuine C++ in headers anyway (e.g. logging interface in petsclog.hh, Exception and Point in petscsys.hh, almost all of Sieve, the few "*.c" files are obviously C++ only and thus should be renamed)?
> 
> If indeed the C++ stuff (apart from Sieve) resides only in headers, we could unconditionally enable it when __cplusplus (so users could do a standard C build of PETSc and then use the "C++ bits" when calling PETSc from C++).