Add HAVE_PETSC macro.

opm/core/linalg/LinearSolverFactory.cpp

@@ -31,7 +31,10 @@
 #include <opm/core/linalg/LinearSolverIstl.hpp>
 #endif
 
+#if HAVE_PETSC
 #include <opm/core/linalg/LinearSolverPetsc.hpp>
+#endif
+
 #include <opm/core/utility/parameters/ParameterGroup.hpp>
 #include <opm/core/utility/ErrorMacros.hpp>
 #include <string>
@@ -46,9 +49,9 @@ namespace Opm
         solver_.reset(new LinearSolverUmfpack);
 #elif HAVE_DUNE_ISTL
         solver_.reset(new LinearSolverIstl);
-#else
+#elif HAVE_PETSC
         solver_.reset(new LinearSolverPetsc);
-
+#else
         OPM_THROW(std::runtime_error, "No linear solver available, you must have UMFPACK , dune-istl or Petsc installed to use LinearSolverFactory.");
 #endif
     }
@@ -73,7 +76,9 @@ namespace Opm
 #endif
         }
         else if (ls == "petsc"){
+#if HAVE_PETSC
             solver_.reset(new LinearSolverPetsc(param));
+#endif
         }
 
         else {