adding error code for problems loading/saving state or autotuning state

elpa/elpa_constants.h.in

@@ -98,7 +98,8 @@ enum ELPA_COMPLEX_KERNELS {
         X(ELPA_ERROR_API_VERSION, -8) \
         X(ELPA_ERROR_AUTOTUNE_API_VERSION, -9) \
         X(ELPA_ERROR_AUTOTUNE_OBJECT_CHANGED, -10) \
-        X(ELPA_ERROR_ENTRY_READONLY, -11)
+        X(ELPA_ERROR_ENTRY_READONLY, -11) \
+        X(ELPA_ERROR_CANNOT_OPEN_FILE, -12)
 
 enum ELPA_ERRORS {
         ELPA_FOR_ALL_ERRORS(ELPA_ENUM_ENTRY)

src/elpa_impl.F90

@@ -1254,7 +1254,7 @@ module elpa_impl
       if (elpa_index_print_settings_c(self%index, file_name // c_null_char) /= 1) then
         write(error_unit, *) "This should not happen (in elpa_store_settings())"
         if (present(error)) then
-          error = ELPA_ERROR
+          error = ELPA_ERROR_CANNOT_OPEN_FILE
         endif
 
       endif
@@ -1300,7 +1300,7 @@ module elpa_impl
       if (elpa_index_load_settings_c(self%index, file_name // c_null_char) /= 1) then
         write(error_unit, *) "This should not happen (in elpa_load_settings())"
         if (present(error)) then
-          error = ELPA_ERROR
+          error = ELPA_ERROR_CANNOT_OPEN_FILE
         endif
       endif
     end subroutine
@@ -1422,7 +1422,7 @@ module elpa_impl
                   ts_impl%min_val, ts_impl%current, ts_impl%cardinality, file_name // c_null_char) /= 1) then
         write(error_unit, *) "This should not happen (in elpa_autotune_save_state())"
         if (present(error)) then
-          error = ELPA_ERROR_AUTOTUNE_OBJECT_CHANGED
+          error = ELPA_ERROR_CANNOT_OPEN_FILE
         endif
       endif
     end subroutine
@@ -1493,7 +1493,7 @@ module elpa_impl
                   ts_impl%min_val, ts_impl%current, ts_impl%cardinality, file_name // c_null_char) /= 1) then
          write(error_unit, *) "This should not happen (in elpa_autotune_load_state())"
         if (present(error)) then
-          error = ELPA_ERROR_AUTOTUNE_OBJECT_CHANGED
+          error = ELPA_ERROR_CANNOT_OPEN_FILE
         endif
       endif
       !print *, "testing, after C call, ts_impl%current is ", ts_impl%current