Intel® Fortran Compiler 16.0 User and Reference Guide
Statement: Separates the body of a main program, module, submodule, or external subprogram from any internal or module procedures it may contain, or it introduces the type-bound procedure part of a derived-type definition. It is not executable.
CONTAINS
Any number of internal procedures can follow a CONTAINS statement, but a CONTAINS statement cannot appear in the internal procedures themselves.
An empty CONTAINS section is allowed.
PROGRAM OUTER REAL, DIMENSION(10) :: A . . . CALL INNER (A) CONTAINS SUBROUTINE INNER (B) REAL, DIMENSION(10) :: B . . . END SUBROUTINE INNER END PROGRAM OUTER