Philippe 08/10/2024: mode_datetime: add elemental or impure elemental attributes

src/MNH/mode_datetime.f90

-!MNH_LIC Copyright 2018-2023 CNRS, Meteo-France and Universite Paul Sabatier
+!MNH_LIC Copyright 2018-2024 CNRS, Meteo-France and Universite Paul Sabatier
 !MNH_LIC This is part of the Meso-NH software governed by the CeCILL-C licence
 !MNH_LIC version 1. See LICENSE, CeCILL-C_V1-en.txt and CeCILL-C_V1-fr.txt
 !MNH_LIC for details. version 1.
@@ -59,7 +59,7 @@ END INTERFACE
 !
 CONTAINS
 !
-SUBROUTINE DATETIME_TIME2REFERENCE( TPDATE, KDAYS, PSEC )
+IMPURE ELEMENTAL SUBROUTINE DATETIME_TIME2REFERENCE( TPDATE, KDAYS, PSEC )
 !
 !Compute number of days and seconds since reference date (and time)
 !Days and seconds are separated to allow correct computation of differences even
@@ -138,7 +138,7 @@ PSEC  = ZSEC
 END SUBROUTINE DATETIME_TIME2REFERENCE
 !
 !
-SUBROUTINE DATETIME_DISTANCE(TPDATEBEG,TPDATEEND,PDIST)
+IMPURE ELEMENTAL SUBROUTINE DATETIME_DISTANCE(TPDATEBEG,TPDATEEND,PDIST)
 !
 !Compute distance (in seconds) between 2 dates
 !
@@ -281,7 +281,7 @@ END SELECT
 END SUBROUTINE DATETIME_GETMONTHLGT
 
 
-FUNCTION DATETIME_LT(TPT1, TPT2) RESULT (OLT)
+IMPURE ELEMENTAL FUNCTION DATETIME_LT(TPT1, TPT2) RESULT (OLT)
 !
 ! TRUE if TPT1 .LT. TPT2
 !
@@ -325,7 +325,7 @@ END IF
 END FUNCTION DATETIME_LT
 
 
-FUNCTION DATETIME_LE(TPT1, TPT2) RESULT (OLE)
+IMPURE ELEMENTAL FUNCTION DATETIME_LE(TPT1, TPT2) RESULT (OLE)
 !
 ! TRUE if TPT1 <= TPT2
 !
@@ -369,7 +369,7 @@ END IF
 END FUNCTION DATETIME_LE
 
 
-FUNCTION DATETIME_GE(TPT1, TPT2) RESULT (OGE)
+IMPURE ELEMENTAL FUNCTION DATETIME_GE(TPT1, TPT2) RESULT (OGE)
 !
 ! TRUE if TPT1 >=. TPT2
 !
@@ -384,7 +384,7 @@ OGE = .NOT. DATETIME_LT( TPT1, TPT2 )
 END FUNCTION DATETIME_GE
 
 
-FUNCTION DATETIME_GT(TPT1, TPT2) RESULT (OGT)
+IMPURE ELEMENTAL FUNCTION DATETIME_GT(TPT1, TPT2) RESULT (OGT)
 !
 ! TRUE if TPT1 > TPT2
 !
@@ -399,7 +399,7 @@ OGT = .NOT. DATETIME_LE( TPT1, TPT2 )
 END FUNCTION DATETIME_GT
 
 
-FUNCTION DATETIME_TIME_ADD( TPIN, PTIME ) RESULT ( TPOUT )
+ELEMENTAL FUNCTION DATETIME_TIME_ADD( TPIN, PTIME ) RESULT ( TPOUT )
 
 IMPLICIT NONE
 
@@ -415,7 +415,7 @@ CALL DATETIME_CORRECTDATE( TPOUT )
 END FUNCTION DATETIME_TIME_ADD
 
 
-FUNCTION DATETIME_TIME_SUBSTRACT( TPT1, TPT2 ) RESULT( PDIST )
+IMPURE ELEMENTAL FUNCTION DATETIME_TIME_SUBSTRACT( TPT1, TPT2 ) RESULT( PDIST )
 !
 !Compute distance (in seconds) between 2 dates
 !