Fix initialization of FFTW

This also fixes the import of wisdom files if they were created by CP2K.

src/pw/fft/fftw3_lib.F

@@ -154,9 +154,8 @@ CONTAINS
       ! only the ionode updates the wisdom
       IF (ionode) THEN
          iunit = get_unit_number()
-         OPEN (UNIT=iunit, FILE=wisdom_file, STATUS="REPLACE", FORM="FORMATTED", ACTION="WRITE", IOSTAT=istat)
+         OPEN (UNIT=iunit, FILE=wisdom_file, STATUS="UNKNOWN", FORM="FORMATTED", ACTION="WRITE", IOSTAT=istat)
          IF (istat == 0) THEN
-            CLOSE (iunit)
             file_name_length = LEN_TRIM(wisdom_file)
             ALLOCATE (wisdom_file_name_c(file_name_length + 1))
             DO i = 1, file_name_length
@@ -166,7 +165,7 @@ CONTAINS
             isuccess = fftw_export_wisdom_to_filename(wisdom_file_name_c)
             IF (isuccess == 0) &
                CPABORT("Error exporting wisdom to file "//wisdom_file)
-            WRITE (*, *) "Exported wisdom to file "//wisdom_file
+            CLOSE (iunit)
          END IF
       END IF
 
@@ -217,6 +216,10 @@ CONTAINS
 #include <mkl_version.h>
 #endif
 
+      isuccess = fftw_init_threads()
+      IF (isuccess == 0) &
+         CPABORT("Error initializing FFTW with threads")
+
       ! Read FFTW wisdom (if available)
       ! all nodes are opening the file here...
       INQUIRE (FILE=wisdom_file, exist=file_exists)
@@ -229,8 +232,8 @@ CONTAINS
          wisdom_file_name_c(file_name_length + 1) = C_NULL_CHAR
          isuccess = fftw_import_wisdom_from_filename(wisdom_file_name_c)
          IF (isuccess == 0) &
-            CPABORT("Error importing wisdom from file "//wisdom_file)
-         WRITE (*, *) "Imported wisdom to file "//wisdom_file
+            CALL cp_abort(__LOCATION__, "Error importing wisdom from file "//wisdom_file//". "// &
+                          "Maybe the was created with a different configuration than CP2K is run with.")
       END IF
 
 #if defined (__MKL)

tests/QS/regtest-fftw-wisdom/TEST_FILES

@@ -0,0 +1,3 @@
+test_wisdom_export.inp                                          11      2e-13            -1.088792073500891
+test_wisdom_import.inp                                          11      2e-13            -1.088792073500891
+#EOF

tests/QS/regtest-fftw-wisdom/test_wisdom_export.inp

@@ -0,0 +1,47 @@
+&GLOBAL
+  FFTW_PLAN_TYPE PATIENT
+  FFTW_WISDOM_FILE_NAME ./wisdom
+  PREFERRED_FFT_LIBRARY FFTW3
+  PRINT_LEVEL MEDIUM
+  PROJECT test_wisdom_export
+  RUN_TYPE ENERGY
+&END GLOBAL
+
+&FORCE_EVAL
+  METHOD Quickstep
+  &DFT
+    BASIS_SET_FILE_NAME BASIS_MOLOPT
+    POTENTIAL_FILE_NAME GTH_POTENTIALS
+    &MGRID
+      CUTOFF 100
+      REL_CUTOFF 30
+    &END MGRID
+    &QS
+      EPS_DEFAULT 1.0E-7
+    &END QS
+    &SCF
+      EPS_SCF 1.0E-6
+    &END SCF
+    &XC
+      &XC_FUNCTIONAL PADE
+      &END XC_FUNCTIONAL
+    &END XC
+  &END DFT
+  &SUBSYS
+    &CELL
+      ABC 4.0 3.0 3.0
+      MULTIPLE_UNIT_CELL 1 1 1
+    &END CELL
+    &COORD
+      H 0.0 0.0 0.0 H
+      H 0.8 0.0 0.0 H
+    &END COORD
+    &KIND H
+      BASIS_SET SZV-MOLOPT-GTH
+      POTENTIAL GTH-PADE-q1
+    &END KIND
+    &TOPOLOGY
+      MULTIPLE_UNIT_CELL 1 1 1
+    &END TOPOLOGY
+  &END SUBSYS
+&END FORCE_EVAL

tests/QS/regtest-fftw-wisdom/test_wisdom_import.inp

@@ -0,0 +1,47 @@
+&GLOBAL
+  FFTW_PLAN_TYPE PATIENT
+  FFTW_WISDOM_FILE_NAME ./wisdom
+  PREFERRED_FFT_LIBRARY FFTW3
+  PRINT_LEVEL MEDIUM
+  PROJECT test_wisdom_export
+  RUN_TYPE ENERGY
+&END GLOBAL
+
+&FORCE_EVAL
+  METHOD Quickstep
+  &DFT
+    BASIS_SET_FILE_NAME BASIS_MOLOPT
+    POTENTIAL_FILE_NAME GTH_POTENTIALS
+    &MGRID
+      CUTOFF 100
+      REL_CUTOFF 30
+    &END MGRID
+    &QS
+      EPS_DEFAULT 1.0E-7
+    &END QS
+    &SCF
+      EPS_SCF 1.0E-6
+    &END SCF
+    &XC
+      &XC_FUNCTIONAL PADE
+      &END XC_FUNCTIONAL
+    &END XC
+  &END DFT
+  &SUBSYS
+    &CELL
+      ABC 4.0 3.0 3.0
+      MULTIPLE_UNIT_CELL 1 1 1
+    &END CELL
+    &COORD
+      H 0.0 0.0 0.0 H
+      H 0.8 0.0 0.0 H
+    &END COORD
+    &KIND H
+      BASIS_SET SZV-MOLOPT-GTH
+      POTENTIAL GTH-PADE-q1
+    &END KIND
+    &TOPOLOGY
+      MULTIPLE_UNIT_CELL 1 1 1
+    &END TOPOLOGY
+  &END SUBSYS
+&END FORCE_EVAL

tests/TEST_DIRS

@@ -3,6 +3,7 @@
 # Directories have been reordered according the execution time needed for a gfortran pdbg run using 2 MPI tasks
 # in case a new directory is added just add it at the top of the list..
 # the order will be regularly checked and modified...
+QS/regtest-fftw-wisdom                                      fftw3
 Fist/regtest-water
 QS/regtest-ecp                                              libgrpp
 QS/regtest-ecp-2                                            libgrpp