gcc/testsuite/gfortran.dg/whole_file_18.f90

   1 ! { dg-do compile }
   2 ! { dg-options "-Wno-unused-dummy-argument" }
   3 !
   4 ! PR fortran/34260
   5 !
   6       PROGRAM MAIN
   7       REAL A
   8       CALL SUB(A)             ! { dg-error "Explicit interface required" }
   9       END PROGRAM
  10
  11       SUBROUTINE SUB(A,I)
  12       REAL :: A
  13       INTEGER, OPTIONAL :: I
  14       END SUBROUTINE