diff --git a/base/modules/psb_c_base_mat_mod.f90 b/base/modules/psb_c_base_mat_mod.f90
index 73486b1f..8dbbbb4b 100644
--- a/base/modules/psb_c_base_mat_mod.f90
+++ b/base/modules/psb_c_base_mat_mod.f90
@@ -432,8 +432,8 @@ module psb_c_base_mat_mod
     subroutine psb_c_base_clone(a,b, info)
       import :: psb_ipk_, psb_c_base_sparse_mat, psb_long_int_k_      
       implicit none 
-      class(psb_c_base_sparse_mat), intent(inout)            :: a
-      class(psb_c_base_sparse_mat), allocatable, intent(out) :: b
+      class(psb_c_base_sparse_mat), intent(inout)              :: a
+      class(psb_c_base_sparse_mat), allocatable, intent(inout) :: b
       integer(psb_ipk_), intent(out)                         :: info      
     end subroutine psb_c_base_clone
   end interface
@@ -1585,8 +1585,6 @@ module psb_c_base_mat_mod
   
 contains 
   
-  
- 
   subroutine c_base_mv_from(a,b)
     
     implicit none 
diff --git a/base/modules/psb_d_base_mat_mod.f90 b/base/modules/psb_d_base_mat_mod.f90
index d2530c4b..d29288a8 100644
--- a/base/modules/psb_d_base_mat_mod.f90
+++ b/base/modules/psb_d_base_mat_mod.f90
@@ -432,8 +432,8 @@ module psb_d_base_mat_mod
     subroutine psb_d_base_clone(a,b, info)
       import :: psb_ipk_, psb_d_base_sparse_mat, psb_long_int_k_      
       implicit none 
-      class(psb_d_base_sparse_mat), intent(inout)            :: a
-      class(psb_d_base_sparse_mat), allocatable, intent(out) :: b
+      class(psb_d_base_sparse_mat), intent(inout)              :: a
+      class(psb_d_base_sparse_mat), allocatable, intent(inout) :: b
       integer(psb_ipk_), intent(out)                         :: info      
     end subroutine psb_d_base_clone
   end interface
@@ -1585,8 +1585,6 @@ module psb_d_base_mat_mod
   
 contains 
   
-  
- 
   subroutine d_base_mv_from(a,b)
     
     implicit none 
diff --git a/base/modules/psb_desc_mod.f90 b/base/modules/psb_desc_mod.f90
index 134cd87c..5c59b708 100644
--- a/base/modules/psb_desc_mod.f90
+++ b/base/modules/psb_desc_mod.f90
@@ -908,9 +908,9 @@ contains
     implicit none
     !....parameters...
 
-    class(psb_desc_type), intent(inout), target  :: desc
-    class(psb_desc_type), intent(out)   :: desc_out
-    integer(psb_ipk_), intent(out)      :: info
+    class(psb_desc_type), intent(inout), target :: desc
+    class(psb_desc_type), intent(inout)         :: desc_out
+    integer(psb_ipk_), intent(out)              :: info
     !locals
     integer(psb_ipk_) :: np,me,ictxt, err_act
     integer(psb_ipk_) :: debug_level, debug_unit
@@ -924,31 +924,42 @@ contains
     call psb_erractionsave(err_act)
     name = 'psb_cdcpy'
 
-    ictxt = desc%get_context()
+    if (desc%is_valid()) then 
+      ictxt = desc%get_context()
 
-    ! check on blacs grid 
-    call psb_info(ictxt, me, np)
-    if (debug_level >= psb_debug_ext_) &
-         & write(debug_unit,*) me,' ',trim(name),': Entered'
-    if (np == -1) then
-      info = psb_err_context_error_
-      call psb_errpush(info,name)
-      goto 9999
-    endif
+      ! check on blacs grid 
+      call psb_info(ictxt, me, np)
+      if (debug_level >= psb_debug_ext_) &
+           & write(debug_unit,*) me,' ',trim(name),': Entered'
+      if (np == -1) then
+        info = psb_err_context_error_
+        call psb_errpush(info,name)
+        goto 9999
+      endif
 
-    desc_out%base_desc  => desc%base_desc
-    if (info == psb_success_) call psb_safe_ab_cpy(desc%halo_index,desc_out%halo_index,info)
-    if (info == psb_success_) call psb_safe_ab_cpy(desc%ext_index,desc_out%ext_index,info)
-    if (info == psb_success_) call psb_safe_ab_cpy(desc%ovrlap_index,&
-         & desc_out%ovrlap_index,info)
-    if (info == psb_success_) call psb_safe_ab_cpy(desc%bnd_elem,desc_out%bnd_elem,info)
-    if (info == psb_success_) call psb_safe_ab_cpy(desc%ovrlap_elem,desc_out%ovrlap_elem,info)
-    if (info == psb_success_) call psb_safe_ab_cpy(desc%ovr_mst_idx,desc_out%ovr_mst_idx,info)
-    if (info == psb_success_) call psb_safe_ab_cpy(desc%lprm,desc_out%lprm,info)
-    if (info == psb_success_) call psb_safe_ab_cpy(desc%idx_space,desc_out%idx_space,info)
-
-    if ((info == psb_success_).and.(allocated(desc%indxmap))) &
-         & call desc%indxmap%clone(desc_out%indxmap,info)
+      desc_out%base_desc  => desc%base_desc
+      if (info == psb_success_)&
+           & call psb_safe_ab_cpy(desc%halo_index,desc_out%halo_index,info)
+      if (info == psb_success_)&
+           & call psb_safe_ab_cpy(desc%ext_index,desc_out%ext_index,info)
+      if (info == psb_success_)&
+           & call psb_safe_ab_cpy(desc%ovrlap_index,&
+           & desc_out%ovrlap_index,info)
+      if (info == psb_success_)&
+           & call psb_safe_ab_cpy(desc%bnd_elem,desc_out%bnd_elem,info)
+      if (info == psb_success_)&
+           & call psb_safe_ab_cpy(desc%ovrlap_elem,desc_out%ovrlap_elem,info)
+      if (info == psb_success_)&
+           & call psb_safe_ab_cpy(desc%ovr_mst_idx,desc_out%ovr_mst_idx,info)
+      if (info == psb_success_)&
+           & call psb_safe_ab_cpy(desc%lprm,desc_out%lprm,info)
+      if (info == psb_success_)&
+           & call psb_safe_ab_cpy(desc%idx_space,desc_out%idx_space,info)
+      if ((info == psb_success_).and.(allocated(desc%indxmap))) &
+           & call desc%indxmap%clone(desc_out%indxmap,info)
+    else
+      call desc_out%free(info)
+    end if
     if (info /= psb_success_) then
       info = psb_err_from_subroutine_
       call psb_errpush(info,name)
diff --git a/base/modules/psb_s_base_mat_mod.f90 b/base/modules/psb_s_base_mat_mod.f90
index 625d20e4..5b8e7b84 100644
--- a/base/modules/psb_s_base_mat_mod.f90
+++ b/base/modules/psb_s_base_mat_mod.f90
@@ -432,8 +432,8 @@ module psb_s_base_mat_mod
     subroutine psb_s_base_clone(a,b, info)
       import :: psb_ipk_, psb_s_base_sparse_mat, psb_long_int_k_      
       implicit none 
-      class(psb_s_base_sparse_mat), intent(inout)            :: a
-      class(psb_s_base_sparse_mat), allocatable, intent(out) :: b
+      class(psb_s_base_sparse_mat), intent(inout)              :: a
+      class(psb_s_base_sparse_mat), allocatable, intent(inout) :: b
       integer(psb_ipk_), intent(out)                         :: info      
     end subroutine psb_s_base_clone
   end interface
@@ -1585,8 +1585,6 @@ module psb_s_base_mat_mod
   
 contains 
   
-  
- 
   subroutine s_base_mv_from(a,b)
     
     implicit none 
diff --git a/base/modules/psb_z_base_mat_mod.f90 b/base/modules/psb_z_base_mat_mod.f90
index 3396675e..49b6c920 100644
--- a/base/modules/psb_z_base_mat_mod.f90
+++ b/base/modules/psb_z_base_mat_mod.f90
@@ -432,8 +432,8 @@ module psb_z_base_mat_mod
     subroutine psb_z_base_clone(a,b, info)
       import :: psb_ipk_, psb_z_base_sparse_mat, psb_long_int_k_      
       implicit none 
-      class(psb_z_base_sparse_mat), intent(inout)            :: a
-      class(psb_z_base_sparse_mat), allocatable, intent(out) :: b
+      class(psb_z_base_sparse_mat), intent(inout)              :: a
+      class(psb_z_base_sparse_mat), allocatable, intent(inout) :: b
       integer(psb_ipk_), intent(out)                         :: info      
     end subroutine psb_z_base_clone
   end interface
@@ -1585,8 +1585,6 @@ module psb_z_base_mat_mod
   
 contains 
   
-  
- 
   subroutine z_base_mv_from(a,b)
     
     implicit none 
diff --git a/base/serial/impl/psb_c_base_mat_impl.F90 b/base/serial/impl/psb_c_base_mat_impl.F90
index 1aec65f6..3e56ed01 100644
--- a/base/serial/impl/psb_c_base_mat_impl.F90
+++ b/base/serial/impl/psb_c_base_mat_impl.F90
@@ -555,10 +555,21 @@ subroutine psb_c_base_clone(a,b,info)
   use psb_error_mod
   implicit none 
   
-  class(psb_c_base_sparse_mat), intent(inout)   :: a
-  class(psb_c_base_sparse_mat), allocatable, intent(out) :: b
+  class(psb_c_base_sparse_mat), intent(inout)              :: a
+  class(psb_c_base_sparse_mat), allocatable, intent(inout) :: b
   integer(psb_ipk_), intent(out) :: info 
 
+  if (allocated(b)) then
+    call b%free()
+    deallocate(b, stat=info)
+  end if
+  if (info /= 0) then 
+    info = psb_err_alloc_dealloc_
+    return
+  end if
+
+  ! Do not use SOURCE allocation: this makes sure that
+  ! memory allocated elsewhere is treated properly. 
 #if defined(HAVE_MOLD)
   allocate(b,mold=a,stat=info)
   if (info /= psb_success_) info = psb_err_alloc_dealloc_
diff --git a/base/serial/impl/psb_d_base_mat_impl.F90 b/base/serial/impl/psb_d_base_mat_impl.F90
index d10212a2..cccf18af 100644
--- a/base/serial/impl/psb_d_base_mat_impl.F90
+++ b/base/serial/impl/psb_d_base_mat_impl.F90
@@ -555,10 +555,21 @@ subroutine psb_d_base_clone(a,b,info)
   use psb_error_mod
   implicit none 
   
-  class(psb_d_base_sparse_mat), intent(inout)   :: a
-  class(psb_d_base_sparse_mat), allocatable, intent(out) :: b
+  class(psb_d_base_sparse_mat), intent(inout)              :: a
+  class(psb_d_base_sparse_mat), allocatable, intent(inout) :: b
   integer(psb_ipk_), intent(out) :: info 
 
+  if (allocated(b)) then
+    call b%free()
+    deallocate(b, stat=info)
+  end if
+  if (info /= 0) then 
+    info = psb_err_alloc_dealloc_
+    return
+  end if
+
+  ! Do not use SOURCE allocation: this makes sure that
+  ! memory allocated elsewhere is treated properly. 
 #if defined(HAVE_MOLD)
   allocate(b,mold=a,stat=info)
   if (info /= psb_success_) info = psb_err_alloc_dealloc_
diff --git a/base/serial/impl/psb_s_base_mat_impl.F90 b/base/serial/impl/psb_s_base_mat_impl.F90
index aa301d63..427cb29c 100644
--- a/base/serial/impl/psb_s_base_mat_impl.F90
+++ b/base/serial/impl/psb_s_base_mat_impl.F90
@@ -555,10 +555,21 @@ subroutine psb_s_base_clone(a,b,info)
   use psb_error_mod
   implicit none 
   
-  class(psb_s_base_sparse_mat), intent(inout)   :: a
-  class(psb_s_base_sparse_mat), allocatable, intent(out) :: b
+  class(psb_s_base_sparse_mat), intent(inout)              :: a
+  class(psb_s_base_sparse_mat), allocatable, intent(inout) :: b
   integer(psb_ipk_), intent(out) :: info 
 
+  if (allocated(b)) then
+    call b%free()
+    deallocate(b, stat=info)
+  end if
+  if (info /= 0) then 
+    info = psb_err_alloc_dealloc_
+    return
+  end if
+
+  ! Do not use SOURCE allocation: this makes sure that
+  ! memory allocated elsewhere is treated properly. 
 #if defined(HAVE_MOLD)
   allocate(b,mold=a,stat=info)
   if (info /= psb_success_) info = psb_err_alloc_dealloc_
diff --git a/base/serial/impl/psb_z_base_mat_impl.F90 b/base/serial/impl/psb_z_base_mat_impl.F90
index d0970056..63b77d7c 100644
--- a/base/serial/impl/psb_z_base_mat_impl.F90
+++ b/base/serial/impl/psb_z_base_mat_impl.F90
@@ -555,10 +555,21 @@ subroutine psb_z_base_clone(a,b,info)
   use psb_error_mod
   implicit none 
   
-  class(psb_z_base_sparse_mat), intent(inout)   :: a
-  class(psb_z_base_sparse_mat), allocatable, intent(out) :: b
+  class(psb_z_base_sparse_mat), intent(inout)              :: a
+  class(psb_z_base_sparse_mat), allocatable, intent(inout) :: b
   integer(psb_ipk_), intent(out) :: info 
 
+  if (allocated(b)) then
+    call b%free()
+    deallocate(b, stat=info)
+  end if
+  if (info /= 0) then 
+    info = psb_err_alloc_dealloc_
+    return
+  end if
+
+  ! Do not use SOURCE allocation: this makes sure that
+  ! memory allocated elsewhere is treated properly. 
 #if defined(HAVE_MOLD)
   allocate(b,mold=a,stat=info)
   if (info /= psb_success_) info = psb_err_alloc_dealloc_