From 08335a8eea374e331f325e2d42caff88da3d57bb Mon Sep 17 00:00:00 2001
From: Salvatore Filippone <salvatore.filippone@cranfield.ac.uk>
Date: Tue, 29 Jan 2019 16:47:21 +0000
Subject: [PATCH] New recursive keyword for all Krylov methods

---
 krylov/psb_cbicg.f90    | 2 +-
 krylov/psb_ccgs.f90     | 2 +-
 krylov/psb_ccgstab.f90  | 2 +-
 krylov/psb_ccgstabl.f90 | 2 +-
 krylov/psb_cfcg.F90     | 2 +-
 krylov/psb_cgcr.f90     | 2 +-
 krylov/psb_ckrylov.f90  | 4 ++--
 krylov/psb_crgmres.f90  | 2 +-
 krylov/psb_dbicg.f90    | 2 +-
 krylov/psb_dcgs.f90     | 2 +-
 krylov/psb_dcgstab.f90  | 2 +-
 krylov/psb_dcgstabl.f90 | 2 +-
 krylov/psb_dfcg.F90     | 2 +-
 krylov/psb_dgcr.f90     | 2 +-
 krylov/psb_dkrylov.f90  | 4 ++--
 krylov/psb_drgmres.f90  | 2 +-
 krylov/psb_sbicg.f90    | 2 +-
 krylov/psb_scgs.f90     | 2 +-
 krylov/psb_scgstab.f90  | 2 +-
 krylov/psb_scgstabl.f90 | 2 +-
 krylov/psb_sfcg.F90     | 2 +-
 krylov/psb_sgcr.f90     | 2 +-
 krylov/psb_skrylov.f90  | 4 ++--
 krylov/psb_srgmres.f90  | 2 +-
 krylov/psb_zbicg.f90    | 2 +-
 krylov/psb_zcgs.f90     | 2 +-
 krylov/psb_zcgstab.f90  | 2 +-
 krylov/psb_zcgstabl.f90 | 2 +-
 krylov/psb_zfcg.F90     | 2 +-
 krylov/psb_zgcr.f90     | 2 +-
 krylov/psb_zkrylov.f90  | 4 ++--
 krylov/psb_zrgmres.f90  | 2 +-
 32 files changed, 36 insertions(+), 36 deletions(-)

diff --git a/krylov/psb_cbicg.f90 b/krylov/psb_cbicg.f90
index bb957ef1..f2e591b5 100644
--- a/krylov/psb_cbicg.f90
+++ b/krylov/psb_cbicg.f90
@@ -94,7 +94,7 @@
 ! 
 !
 
-subroutine psb_cbicg_vect(a,prec,b,x,eps,desc_a,info,&
+recursive subroutine psb_cbicg_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_ccgs.f90 b/krylov/psb_ccgs.f90
index b6542aae..5ebed145 100644
--- a/krylov/psb_ccgs.f90
+++ b/krylov/psb_ccgs.f90
@@ -92,7 +92,7 @@
 !                                         where r is the (preconditioned, recursive
 !                                         estimate of) residual. 
 !
-Subroutine psb_ccgs_vect(a,prec,b,x,eps,desc_a,info,&
+recursive Subroutine psb_ccgs_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_ccgstab.f90 b/krylov/psb_ccgstab.f90
index 9cbc3f90..d03ee885 100644
--- a/krylov/psb_ccgstab.f90
+++ b/krylov/psb_ccgstab.f90
@@ -93,7 +93,7 @@
 !                                         where r is the (preconditioned, recursive
 !                                         estimate of) residual. 
 !
-Subroutine psb_ccgstab_vect(a,prec,b,x,eps,desc_a,info,itmax,iter,err,itrace,istop)
+recursive Subroutine psb_ccgstab_vect(a,prec,b,x,eps,desc_a,info,itmax,iter,err,itrace,istop)
   use psb_base_mod
   use psb_prec_mod
   use psb_c_krylov_conv_mod
diff --git a/krylov/psb_ccgstabl.f90 b/krylov/psb_ccgstabl.f90
index 8ab0453a..d9792621 100644
--- a/krylov/psb_ccgstabl.f90
+++ b/krylov/psb_ccgstabl.f90
@@ -103,7 +103,7 @@
 !
 !
 !
-Subroutine psb_ccgstabl_vect(a,prec,b,x,eps,desc_a,info,&
+recursive Subroutine psb_ccgstabl_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,irst,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_cfcg.F90 b/krylov/psb_cfcg.F90
index 16579e6d..5efaaf25 100644
--- a/krylov/psb_cfcg.F90
+++ b/krylov/psb_cfcg.F90
@@ -101,7 +101,7 @@
 !                                            stopped when  |r| <= eps * |b|
 !                                         where r is the (preconditioned, recursive
 !                                         estimate of) residual. 
-!
+! 
 !
 recursive subroutine psb_cfcg_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,istop,cond)
diff --git a/krylov/psb_cgcr.f90 b/krylov/psb_cgcr.f90
index 1ce78fc3..094e59b9 100644
--- a/krylov/psb_cgcr.f90
+++ b/krylov/psb_cgcr.f90
@@ -105,7 +105,7 @@
 !    irst   -  integer(optional)          Input: restart parameter 
 !
 
-subroutine psb_cgcr_vect(a,prec,b,x,eps,desc_a,info,&
+recursive subroutine psb_cgcr_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace, irst, istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_ckrylov.f90 b/krylov/psb_ckrylov.f90
index dd86a387..32063ae9 100644
--- a/krylov/psb_ckrylov.f90
+++ b/krylov/psb_ckrylov.f90
@@ -99,7 +99,7 @@ Subroutine psb_ckrylov_vect(method,a,prec,b,x,eps,desc_a,info,&
 
 
   abstract interface
-    subroutine psb_ckryl_vect(a,prec,b,x,eps,&
+    recursive subroutine psb_ckryl_vect(a,prec,b,x,eps,&
          & desc_a,info,itmax,iter,err,itrace,istop)
       import :: psb_ipk_, psb_spk_, psb_desc_type, &
            & psb_cspmat_type, psb_cprec_type, psb_c_vect_type
@@ -114,7 +114,7 @@ Subroutine psb_ckrylov_vect(method,a,prec,b,x,eps,desc_a,info,&
       integer(psb_ipk_), optional, intent(out)       :: iter
       real(psb_spk_), optional, intent(out) :: err
     end subroutine psb_ckryl_vect
-    Subroutine psb_ckryl_rest_vect(a,prec,b,x,eps,desc_a,info,&
+    recursive Subroutine psb_ckryl_rest_vect(a,prec,b,x,eps,desc_a,info,&
          &itmax,iter,err, itrace,irst,istop)
       import :: psb_ipk_, psb_spk_, psb_desc_type, &
            & psb_cspmat_type, psb_cprec_type, psb_c_vect_type
diff --git a/krylov/psb_crgmres.f90 b/krylov/psb_crgmres.f90
index f68dc74b..cd63c852 100644
--- a/krylov/psb_crgmres.f90
+++ b/krylov/psb_crgmres.f90
@@ -106,7 +106,7 @@
 !    irst   -  integer(optional)          Input: restart parameter 
 !
 
-subroutine psb_crgmres_vect(a,prec,b,x,eps,desc_a,info,&
+recursive subroutine psb_crgmres_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,irst,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_dbicg.f90 b/krylov/psb_dbicg.f90
index be2ed48f..c9fe2906 100644
--- a/krylov/psb_dbicg.f90
+++ b/krylov/psb_dbicg.f90
@@ -94,7 +94,7 @@
 ! 
 !
 
-subroutine psb_dbicg_vect(a,prec,b,x,eps,desc_a,info,&
+recursive subroutine psb_dbicg_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_dcgs.f90 b/krylov/psb_dcgs.f90
index dca1748b..44df19df 100644
--- a/krylov/psb_dcgs.f90
+++ b/krylov/psb_dcgs.f90
@@ -92,7 +92,7 @@
 !                                         where r is the (preconditioned, recursive
 !                                         estimate of) residual. 
 !
-Subroutine psb_dcgs_vect(a,prec,b,x,eps,desc_a,info,&
+recursive Subroutine psb_dcgs_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_dcgstab.f90 b/krylov/psb_dcgstab.f90
index 73b0662d..e1815138 100644
--- a/krylov/psb_dcgstab.f90
+++ b/krylov/psb_dcgstab.f90
@@ -93,7 +93,7 @@
 !                                         where r is the (preconditioned, recursive
 !                                         estimate of) residual. 
 !
-Subroutine psb_dcgstab_vect(a,prec,b,x,eps,desc_a,info,itmax,iter,err,itrace,istop)
+recursive Subroutine psb_dcgstab_vect(a,prec,b,x,eps,desc_a,info,itmax,iter,err,itrace,istop)
   use psb_base_mod
   use psb_prec_mod
   use psb_d_krylov_conv_mod
diff --git a/krylov/psb_dcgstabl.f90 b/krylov/psb_dcgstabl.f90
index c85f562b..175f2878 100644
--- a/krylov/psb_dcgstabl.f90
+++ b/krylov/psb_dcgstabl.f90
@@ -103,7 +103,7 @@
 !
 !
 !
-Subroutine psb_dcgstabl_vect(a,prec,b,x,eps,desc_a,info,&
+recursive Subroutine psb_dcgstabl_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,irst,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_dfcg.F90 b/krylov/psb_dfcg.F90
index c64e6193..188f0337 100644
--- a/krylov/psb_dfcg.F90
+++ b/krylov/psb_dfcg.F90
@@ -101,7 +101,7 @@
 !                                            stopped when  |r| <= eps * |b|
 !                                         where r is the (preconditioned, recursive
 !                                         estimate of) residual. 
-!
+! 
 !
 recursive subroutine psb_dfcg_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,istop,cond)
diff --git a/krylov/psb_dgcr.f90 b/krylov/psb_dgcr.f90
index acbaa5a7..e73b3837 100644
--- a/krylov/psb_dgcr.f90
+++ b/krylov/psb_dgcr.f90
@@ -105,7 +105,7 @@
 !    irst   -  integer(optional)          Input: restart parameter 
 !
 
-subroutine psb_dgcr_vect(a,prec,b,x,eps,desc_a,info,&
+recursive subroutine psb_dgcr_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace, irst, istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_dkrylov.f90 b/krylov/psb_dkrylov.f90
index 53f3702e..0dff1af0 100644
--- a/krylov/psb_dkrylov.f90
+++ b/krylov/psb_dkrylov.f90
@@ -99,7 +99,7 @@ Subroutine psb_dkrylov_vect(method,a,prec,b,x,eps,desc_a,info,&
 
 
   abstract interface
-    subroutine psb_dkryl_vect(a,prec,b,x,eps,&
+    recursive subroutine psb_dkryl_vect(a,prec,b,x,eps,&
          & desc_a,info,itmax,iter,err,itrace,istop)
       import :: psb_ipk_, psb_dpk_, psb_desc_type, &
            & psb_dspmat_type, psb_dprec_type, psb_d_vect_type
@@ -114,7 +114,7 @@ Subroutine psb_dkrylov_vect(method,a,prec,b,x,eps,desc_a,info,&
       integer(psb_ipk_), optional, intent(out)       :: iter
       real(psb_dpk_), optional, intent(out) :: err
     end subroutine psb_dkryl_vect
-    Subroutine psb_dkryl_rest_vect(a,prec,b,x,eps,desc_a,info,&
+    recursive Subroutine psb_dkryl_rest_vect(a,prec,b,x,eps,desc_a,info,&
          &itmax,iter,err, itrace,irst,istop)
       import :: psb_ipk_, psb_dpk_, psb_desc_type, &
            & psb_dspmat_type, psb_dprec_type, psb_d_vect_type
diff --git a/krylov/psb_drgmres.f90 b/krylov/psb_drgmres.f90
index 9b577903..e52c7df8 100644
--- a/krylov/psb_drgmres.f90
+++ b/krylov/psb_drgmres.f90
@@ -106,7 +106,7 @@
 !    irst   -  integer(optional)          Input: restart parameter 
 !
 
-subroutine psb_drgmres_vect(a,prec,b,x,eps,desc_a,info,&
+recursive subroutine psb_drgmres_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,irst,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_sbicg.f90 b/krylov/psb_sbicg.f90
index 2afaa716..b4779bf2 100644
--- a/krylov/psb_sbicg.f90
+++ b/krylov/psb_sbicg.f90
@@ -94,7 +94,7 @@
 ! 
 !
 
-subroutine psb_sbicg_vect(a,prec,b,x,eps,desc_a,info,&
+recursive subroutine psb_sbicg_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_scgs.f90 b/krylov/psb_scgs.f90
index d053444a..30460244 100644
--- a/krylov/psb_scgs.f90
+++ b/krylov/psb_scgs.f90
@@ -92,7 +92,7 @@
 !                                         where r is the (preconditioned, recursive
 !                                         estimate of) residual. 
 !
-Subroutine psb_scgs_vect(a,prec,b,x,eps,desc_a,info,&
+recursive Subroutine psb_scgs_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_scgstab.f90 b/krylov/psb_scgstab.f90
index c0ca345c..36c5b462 100644
--- a/krylov/psb_scgstab.f90
+++ b/krylov/psb_scgstab.f90
@@ -93,7 +93,7 @@
 !                                         where r is the (preconditioned, recursive
 !                                         estimate of) residual. 
 !
-Subroutine psb_scgstab_vect(a,prec,b,x,eps,desc_a,info,itmax,iter,err,itrace,istop)
+recursive Subroutine psb_scgstab_vect(a,prec,b,x,eps,desc_a,info,itmax,iter,err,itrace,istop)
   use psb_base_mod
   use psb_prec_mod
   use psb_s_krylov_conv_mod
diff --git a/krylov/psb_scgstabl.f90 b/krylov/psb_scgstabl.f90
index 0f888980..6b6f6949 100644
--- a/krylov/psb_scgstabl.f90
+++ b/krylov/psb_scgstabl.f90
@@ -103,7 +103,7 @@
 !
 !
 !
-Subroutine psb_scgstabl_vect(a,prec,b,x,eps,desc_a,info,&
+recursive Subroutine psb_scgstabl_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,irst,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_sfcg.F90 b/krylov/psb_sfcg.F90
index 6af103dc..d3d582b8 100644
--- a/krylov/psb_sfcg.F90
+++ b/krylov/psb_sfcg.F90
@@ -101,7 +101,7 @@
 !                                            stopped when  |r| <= eps * |b|
 !                                         where r is the (preconditioned, recursive
 !                                         estimate of) residual. 
-!
+! 
 !
 recursive subroutine psb_sfcg_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,istop,cond)
diff --git a/krylov/psb_sgcr.f90 b/krylov/psb_sgcr.f90
index 08333af2..bcff94f6 100644
--- a/krylov/psb_sgcr.f90
+++ b/krylov/psb_sgcr.f90
@@ -105,7 +105,7 @@
 !    irst   -  integer(optional)          Input: restart parameter 
 !
 
-subroutine psb_sgcr_vect(a,prec,b,x,eps,desc_a,info,&
+recursive subroutine psb_sgcr_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace, irst, istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_skrylov.f90 b/krylov/psb_skrylov.f90
index feb6b759..ce69e48a 100644
--- a/krylov/psb_skrylov.f90
+++ b/krylov/psb_skrylov.f90
@@ -99,7 +99,7 @@ Subroutine psb_skrylov_vect(method,a,prec,b,x,eps,desc_a,info,&
 
 
   abstract interface
-    subroutine psb_skryl_vect(a,prec,b,x,eps,&
+    recursive subroutine psb_skryl_vect(a,prec,b,x,eps,&
          & desc_a,info,itmax,iter,err,itrace,istop)
       import :: psb_ipk_, psb_spk_, psb_desc_type, &
            & psb_sspmat_type, psb_sprec_type, psb_s_vect_type
@@ -114,7 +114,7 @@ Subroutine psb_skrylov_vect(method,a,prec,b,x,eps,desc_a,info,&
       integer(psb_ipk_), optional, intent(out)       :: iter
       real(psb_spk_), optional, intent(out) :: err
     end subroutine psb_skryl_vect
-    Subroutine psb_skryl_rest_vect(a,prec,b,x,eps,desc_a,info,&
+    recursive Subroutine psb_skryl_rest_vect(a,prec,b,x,eps,desc_a,info,&
          &itmax,iter,err, itrace,irst,istop)
       import :: psb_ipk_, psb_spk_, psb_desc_type, &
            & psb_sspmat_type, psb_sprec_type, psb_s_vect_type
diff --git a/krylov/psb_srgmres.f90 b/krylov/psb_srgmres.f90
index 2e458d82..aa941322 100644
--- a/krylov/psb_srgmres.f90
+++ b/krylov/psb_srgmres.f90
@@ -106,7 +106,7 @@
 !    irst   -  integer(optional)          Input: restart parameter 
 !
 
-subroutine psb_srgmres_vect(a,prec,b,x,eps,desc_a,info,&
+recursive subroutine psb_srgmres_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,irst,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_zbicg.f90 b/krylov/psb_zbicg.f90
index 969280d3..032bf4ea 100644
--- a/krylov/psb_zbicg.f90
+++ b/krylov/psb_zbicg.f90
@@ -94,7 +94,7 @@
 ! 
 !
 
-subroutine psb_zbicg_vect(a,prec,b,x,eps,desc_a,info,&
+recursive subroutine psb_zbicg_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_zcgs.f90 b/krylov/psb_zcgs.f90
index 3130427a..1ff4e678 100644
--- a/krylov/psb_zcgs.f90
+++ b/krylov/psb_zcgs.f90
@@ -92,7 +92,7 @@
 !                                         where r is the (preconditioned, recursive
 !                                         estimate of) residual. 
 !
-Subroutine psb_zcgs_vect(a,prec,b,x,eps,desc_a,info,&
+recursive Subroutine psb_zcgs_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_zcgstab.f90 b/krylov/psb_zcgstab.f90
index 68381c48..95d7b53e 100644
--- a/krylov/psb_zcgstab.f90
+++ b/krylov/psb_zcgstab.f90
@@ -93,7 +93,7 @@
 !                                         where r is the (preconditioned, recursive
 !                                         estimate of) residual. 
 !
-Subroutine psb_zcgstab_vect(a,prec,b,x,eps,desc_a,info,itmax,iter,err,itrace,istop)
+recursive Subroutine psb_zcgstab_vect(a,prec,b,x,eps,desc_a,info,itmax,iter,err,itrace,istop)
   use psb_base_mod
   use psb_prec_mod
   use psb_z_krylov_conv_mod
diff --git a/krylov/psb_zcgstabl.f90 b/krylov/psb_zcgstabl.f90
index 5ddbf309..bcec546e 100644
--- a/krylov/psb_zcgstabl.f90
+++ b/krylov/psb_zcgstabl.f90
@@ -103,7 +103,7 @@
 !
 !
 !
-Subroutine psb_zcgstabl_vect(a,prec,b,x,eps,desc_a,info,&
+recursive Subroutine psb_zcgstabl_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,irst,istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_zfcg.F90 b/krylov/psb_zfcg.F90
index dd56d68f..37d6c47d 100644
--- a/krylov/psb_zfcg.F90
+++ b/krylov/psb_zfcg.F90
@@ -101,7 +101,7 @@
 !                                            stopped when  |r| <= eps * |b|
 !                                         where r is the (preconditioned, recursive
 !                                         estimate of) residual. 
-!
+! 
 !
 recursive subroutine psb_zfcg_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,istop,cond)
diff --git a/krylov/psb_zgcr.f90 b/krylov/psb_zgcr.f90
index 40b4cf7f..314d2830 100644
--- a/krylov/psb_zgcr.f90
+++ b/krylov/psb_zgcr.f90
@@ -105,7 +105,7 @@
 !    irst   -  integer(optional)          Input: restart parameter 
 !
 
-subroutine psb_zgcr_vect(a,prec,b,x,eps,desc_a,info,&
+recursive subroutine psb_zgcr_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace, irst, istop)
   use psb_base_mod
   use psb_prec_mod
diff --git a/krylov/psb_zkrylov.f90 b/krylov/psb_zkrylov.f90
index 0ae6e5f5..09be68dd 100644
--- a/krylov/psb_zkrylov.f90
+++ b/krylov/psb_zkrylov.f90
@@ -99,7 +99,7 @@ Subroutine psb_zkrylov_vect(method,a,prec,b,x,eps,desc_a,info,&
 
 
   abstract interface
-    subroutine psb_zkryl_vect(a,prec,b,x,eps,&
+    recursive subroutine psb_zkryl_vect(a,prec,b,x,eps,&
          & desc_a,info,itmax,iter,err,itrace,istop)
       import :: psb_ipk_, psb_dpk_, psb_desc_type, &
            & psb_zspmat_type, psb_zprec_type, psb_z_vect_type
@@ -114,7 +114,7 @@ Subroutine psb_zkrylov_vect(method,a,prec,b,x,eps,desc_a,info,&
       integer(psb_ipk_), optional, intent(out)       :: iter
       real(psb_dpk_), optional, intent(out) :: err
     end subroutine psb_zkryl_vect
-    Subroutine psb_zkryl_rest_vect(a,prec,b,x,eps,desc_a,info,&
+    recursive Subroutine psb_zkryl_rest_vect(a,prec,b,x,eps,desc_a,info,&
          &itmax,iter,err, itrace,irst,istop)
       import :: psb_ipk_, psb_dpk_, psb_desc_type, &
            & psb_zspmat_type, psb_zprec_type, psb_z_vect_type
diff --git a/krylov/psb_zrgmres.f90 b/krylov/psb_zrgmres.f90
index 10738699..eea9369f 100644
--- a/krylov/psb_zrgmres.f90
+++ b/krylov/psb_zrgmres.f90
@@ -106,7 +106,7 @@
 !    irst   -  integer(optional)          Input: restart parameter 
 !
 
-subroutine psb_zrgmres_vect(a,prec,b,x,eps,desc_a,info,&
+recursive subroutine psb_zrgmres_vect(a,prec,b,x,eps,desc_a,info,&
      & itmax,iter,err,itrace,irst,istop)
   use psb_base_mod
   use psb_prec_mod