gfortran-bug.f

c Bug 1:
c Mistakenly initialising unspecified common variable.

      program nblock
      integer x, y
      common /name/x, y
      call hello
      call mello
      print *, x, y
      end

      subroutine hello
      common /name/x, y
      integer x, y
c data statement treats y as initialised as well
c so when it is initialised in the other subroutine
c the value remains 0.
      data x/2/
      return
      end

      subroutine mello
      common /name/x, y
      integer x, y
      data y/15/
      return
      end

c Bug 2:
c Missing error message.

      program nblock
      integer x, y
      common /name/x, y
      print *, x, y
      end

      block data hello
      common /name/x, y
      integer x, y
      data x/2/
      end

c Here the common block with /name/ should throw an error
c as it has been used in a different block data subprogram
c the specification prohibits this use case.
      block data mello
      common /name/x, y
      integer x, y
      data y/15/
      end