title: Compiling Multiple Files with modules
body: <p>I am programming in Fortran 90 using GFortran and I'm having troubles with Modules. When I compile the code below, I get the following error:</p>
  
  <pre><code>Derivatives.f90:7.16:
  Included at C:\Users\dchalhub\Dropbox\Doutorado\#Tese\New folder\main.f90:1:
      Use Mesh
              1
  Fatal Error: Can't open module file 'mesh.mod' for reading at (1): No such file or directory
  gfortran.exe: Internal error: Aborted (program f951)
  Please submit a full bug report.
  See &lt;http://gcc.gnu.org/bugs.html&gt; for instructions.
  </code></pre>
  
  <p>So, the 'mesh.mod' file is not created.
  But when I remove the first two lines: 'include 'Derivatives.f90'' and 'include 'Poisson.f90'' the module is created without any problems. </p>
  
  <p>After the mod file is created, I put back the first two lines, compile the code again and it works perfectly.</p>
  
  <pre><code>include 'Derivatives.f90'
  include 'Poisson.f90'
  
  !**************************************************************
  MODULE MESH
  IMPLICIT NONE
  INTEGER :: IMAX,JMAX,NMAX
  REAL(8), ALLOCATABLE :: XD(:),YD(:),FX(:,:),FY(:,:)
  REAL(8) :: PI,E,DX,DY,H,L,RHO,MU
  PARAMETER (PI = ACOS(-1.D0))
  PARAMETER (E = 2.71828182845904523536028747135266249775724709369995)
  END MODULE MESH
  !**************************************************************
  
  
  
  !**************************************************************
  !*********** Lid-driven Cavity Program*************************
  !**************************************************************
  program Cavity
  Use Mesh
  implicit none
  
  
  End program Cavity
  </code></pre>
  
  <p>I don't know why but there is something wrong with compiling multiple files with modules.
  Does any one know what should I do to make it work properly?</p>