Guard Belos code with macros

cmake/configure/configure_20_trilinos.cmake

@@ -150,7 +150,7 @@ MACRO(FEATURE_TRILINOS_FIND_EXTERNAL var)
       #
       # Check for modules.
       #
-      FOREACH(_optional_module EpetraExt Kokkos MueLu ROL Sacado SEACAS Tpetra Zoltan)
+      FOREACH(_optional_module Belos EpetraExt Kokkos MueLu ROL Sacado SEACAS Tpetra Zoltan)
         ITEM_MATCHES(_module_found ${_optional_module} ${Trilinos_PACKAGE_LIST})
         IF(_module_found)
           MESSAGE(STATUS "  Found ${_optional_module}")

include/deal.II/base/config.h.in

@@ -239,6 +239,7 @@
 
 /* cmake/configure/configure_2_trilinos.cmake */
 #cmakedefine DEAL_II_TRILINOS_CXX_SUPPORTS_SACADO_COMPLEX_RAD
+#cmakedefine DEAL_II_TRILINOS_WITH_BELOS
 #cmakedefine DEAL_II_TRILINOS_WITH_EPETRAEXT
 #cmakedefine DEAL_II_TRILINOS_WITH_MUELU
 #cmakedefine DEAL_II_TRILINOS_WITH_ROL

include/deal.II/lac/trilinos_solver.h

@@ -33,13 +33,15 @@
 #  include <Epetra_Operator.h>
 
 // for Belos solvers
+#ifdef DEAL_II_TRILINOS_WITH_BELOS
 #  include <BelosBlockCGSolMgr.hpp>
 #  include <BelosBlockGmresSolMgr.hpp>
 #  include <BelosEpetraAdapter.hpp>
 #  include <BelosIteration.hpp>
 #  include <BelosMultiVec.hpp>
 #  include <BelosOperator.hpp>
 #  include <BelosSolverManager.hpp>
+#endif
 
 #  include <memory>
 
@@ -730,6 +732,7 @@ namespace TrilinosWrappers
 
 
 
+#ifdef DEAL_II_TRILINOS_WITH_BELOS
   /**
    * Wrapper around the iterate solver package from the Belos
    * packge
@@ -805,13 +808,15 @@ namespace TrilinosWrappers
     const AdditionalData                        additional_data;
     const Teuchos::RCP<Teuchos::ParameterList> &belos_parameters;
   };
+#endif
 
 } // namespace TrilinosWrappers
 
 
 
 #  ifndef DOXYGEN
 
+#ifdef DEAL_II_TRILINOS_WITH_BELOS
 namespace TrilinosWrappers
 {
   namespace internal
@@ -1429,6 +1434,7 @@ namespace TrilinosWrappers
   }
 
 } // namespace TrilinosWrappers
+#endif
 
 #  endif
 

tests/belos/CMakeLists.txt

@@ -0,0 +1,7 @@
+CMAKE_MINIMUM_REQUIRED(VERSION 3.3.0)
+INCLUDE(../setup_testsubproject.cmake)
+PROJECT(testsuite CXX)
+
+IF(DEAL_II_WITH_TRILINOS AND DEAL_II_TRILINOS_WITH_BELOS)
+  DEAL_II_PICKUP_TESTS()
+ENDIF()