dealii: support 64bit BLAS (spack#6758)

var/spack/repos/builtin/packages/dealii/package.py

@@ -151,6 +151,9 @@ class Dealii(CMakePackage, CudaPackage):
     depends_on('trilinos+amesos+aztec+epetra+ifpack+ml+muelu+rol+sacado+teuchos~hypre', when='+trilinos+mpi+int64')
 
     # check that the combination of variants makes sense
+    conflicts('^openblas+ilp64', when='@:8.5.1')
+    conflicts('^intel-mkl+ilp64', when='@:8.5.1')
+    conflicts('^intel-parallel-studio+mkl+ilp64', when='@:8.5.1')
     conflicts('+assimp', when='@:8.5.1')
     conflicts('+gmsh', when='@:8.5.1')
     conflicts('+nanoflann', when='@:8.5.1')
@@ -190,6 +193,11 @@ def cmake_args(self):
             '-DDEAL_II_ALLOW_BUNDLED=OFF'
         ])
 
+        if (spec.satisfies('^openblas+ilp64') or
+            spec.satisfies('^intel-mkl+ilp64') or
+            spec.satisfies('^intel-parallel-studio+mkl+ilp64')):
+            options.append('-DLAPACK_WITH_64BIT_BLAS_INDICES=ON')
+
         if spec.satisfies('@:8.99'):
             options.extend([
                 # Cmake may still pick up system's bzip2, fix this:
@@ -270,7 +278,7 @@ def cmake_args(self):
         for library in (
                 'gsl', 'hdf5', 'p4est', 'petsc', 'slepc', 'trilinos', 'metis',
                 'sundials', 'nanoflann', 'assimp', 'gmsh'):
-            if library in spec:
+            if ('+' + library) in spec:
                 options.extend([
                     '-D%s_DIR=%s' % (library.upper(), spec[library].prefix),
                     '-DDEAL_II_WITH_%s:BOOL=ON' % library.upper()