Calling function in same module in Fortran90

I am new to Fortran90 and I haven't found an answer to a problem I have. I have a module written in Fortran with the some functions inside a module.

Stripped down version:

module vdiStringFunctions


interface vdiString
    module procedure vdiString1Char
  end interface

contains
    character (128) function vdiString1Char(CSTRING, sVar1)
      character(*), intent(in) :: CSTRING, sVar1
      character(128) :: vdiStringGeneral
      character(len=128), dimension(0:9) :: stringArray

  stringArray(0) = adjustl(sVar1)
  vdiString1Char= vdiStringGeneral(CSTRING, stringArray)
end function vdiString1Char

character (128) function vdiStringGeneral(CSTRING, varArray)
  character(*), intent(in) :: CSTRING
  character(len=128), dimension(0:9), intent(in) :: varArray
  vdiStringGeneral = 'bla'
end function vdiStringGeneral 

end module vdiStringFunctions

When I try to compile with Intel Visual Fortran XE 2011 I get the following error:

error LNK2019: unresolved external symbol _VDISTRINGGENERAL referenced in function _VDISTRINGFUNCTIONS_mp_VDISTRING1CHAR vdiStringFunctions.obj

Because the function vdiStringGeneral is in the same module than the calling vdiString1Char I do not get the problem. When I move the vdiStringGeneral outside of the module it compiles without problems.

Because it should be used in a DLL all functions should be inside开发者_开发问答 the module. How can I get it to work that way?

Remove the declaration of vdiStringGeneral in function vdiString1Char. The interface for vdiStringGeneral is already explicit, because it is defined in the same module. With the declaration you have now, the linker is looking for an external function.