[Cython] Issues with CYTHON_FALLTHROUGH

[Lisandro Dalcin]

This is from a conda-forge build of petsc4py on Travis-CI with
"osx_image: xcode6.4"

https://travis-ci.org/conda-forge/petsc4py-feedstock/jobs/287563030


Maybe a better definition is the one below?

  #ifndef CYTHON_FALLTHROUGH
    #if defined(__clang__) && __has_attribute(fallthrough)
      #define CYTHON_FALLTHROUGH __attribute__((fallthrough))
    #elif defined(__GNUC__) && defined(__attribute__)
      #define CYTHON_FALLTHROUGH __attribute__((fallthrough))
    #else
      #define CYTHON_FALLTHROUGH
    #endif
  #endif


-- 
Lisandro Dalcin
============
Research Scientist
Computer, Electrical and Mathematical Sciences & Engineering (CEMSE)
Extreme Computing Research Center (ECRC)
King Abdullah University of Science and Technology (KAUST)
http://ecrc.kaust.edu.sa/

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