Cf. http://gcc.gnu.org/ml/fortran/2007-02/msg00145.html
The following code is invalid Fortran as the USE-associated NAMELIST is respecified in the main program: ---------------------------- MODULE debug LOGICAL debug_area NAMELIST/debugging/debug_area END MODULE debug PROGRAM ding USE debug IMPLICIT NONE NAMELIST/debugging/debug_area INTEGER :: ios OPEN(unit=10, status='unknown', file='input.dat') READ(unit=10, nml=debugging, iostat=ios) PRINT*, 'nml=debugging',ios END PROGRAM ding ---------------------------- Gfortran and Portland group Fortran accept it by default, while xlf, ifort, NAG f95 and g95 reject it by default. Note that gfortran rejects it with -std=f2003: Error: Namelist group name 'debugging' at (1) already is USE associated and cannot be respecified. Should the GFC_STD_GNU be changed into GFC_STD_LEGACY? Or should there be a warning only for -std=gnu (= default option)? Or keep status quo? -- Summary: Warn by default when respecifiying USE associated NAMELIST Product: gcc Version: 4.3.0 Status: UNCONFIRMED Keywords: diagnostic Severity: normal Priority: P3 Component: fortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: burnus at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30923