diff --git a/base/serial/impl/psb_c_coo_impl.f90 b/base/serial/impl/psb_c_coo_impl.f90
index fa9fa093..4b328ef3 100644
--- a/base/serial/impl/psb_c_coo_impl.f90
+++ b/base/serial/impl/psb_c_coo_impl.f90
@@ -3463,7 +3463,7 @@ subroutine psb_c_fix_coo_inner(nr,nc,nzin,dupl,ia,ja,val,nzout,info,idir)
     goto 9999
   end if
 
-  allocate(ias(nzin),jas(nzin),vs(nzin),ix2(max(nr,nc,nzin)), stat=info)
+  allocate(ias(nzin),jas(nzin),vs(nzin),ix2(max(nr,nc,nzin)+2), stat=info)
   use_buffers = (info == 0)
   
   select case(idir_) 
diff --git a/base/serial/impl/psb_d_coo_impl.f90 b/base/serial/impl/psb_d_coo_impl.f90
index 636712dd..428cc9f8 100644
--- a/base/serial/impl/psb_d_coo_impl.f90
+++ b/base/serial/impl/psb_d_coo_impl.f90
@@ -3463,7 +3463,7 @@ subroutine psb_d_fix_coo_inner(nr,nc,nzin,dupl,ia,ja,val,nzout,info,idir)
     goto 9999
   end if
 
-  allocate(ias(nzin),jas(nzin),vs(nzin),ix2(max(nr,nc,nzin)), stat=info)
+  allocate(ias(nzin),jas(nzin),vs(nzin),ix2(max(nr,nc,nzin)+2), stat=info)
   use_buffers = (info == 0)
   
   select case(idir_) 
diff --git a/base/serial/impl/psb_s_coo_impl.f90 b/base/serial/impl/psb_s_coo_impl.f90
index 9678849e..4f16f90e 100644
--- a/base/serial/impl/psb_s_coo_impl.f90
+++ b/base/serial/impl/psb_s_coo_impl.f90
@@ -3463,7 +3463,7 @@ subroutine psb_s_fix_coo_inner(nr,nc,nzin,dupl,ia,ja,val,nzout,info,idir)
     goto 9999
   end if
 
-  allocate(ias(nzin),jas(nzin),vs(nzin),ix2(max(nr,nc,nzin)), stat=info)
+  allocate(ias(nzin),jas(nzin),vs(nzin),ix2(max(nr,nc,nzin)+2), stat=info)
   use_buffers = (info == 0)
   
   select case(idir_) 
diff --git a/base/serial/impl/psb_z_coo_impl.f90 b/base/serial/impl/psb_z_coo_impl.f90
index 982ad042..2af0afce 100644
--- a/base/serial/impl/psb_z_coo_impl.f90
+++ b/base/serial/impl/psb_z_coo_impl.f90
@@ -3463,7 +3463,7 @@ subroutine psb_z_fix_coo_inner(nr,nc,nzin,dupl,ia,ja,val,nzout,info,idir)
     goto 9999
   end if
 
-  allocate(ias(nzin),jas(nzin),vs(nzin),ix2(max(nr,nc,nzin)), stat=info)
+  allocate(ias(nzin),jas(nzin),vs(nzin),ix2(max(nr,nc,nzin)+2), stat=info)
   use_buffers = (info == 0)
   
   select case(idir_)