[Scons-users] ifort (maybe general Fortran): Module directory issues

[Markus Hrywniak]

Hi everybody,

I'm enjoying the scons experience so far, the automatic dependency 
tracking is especially cool.
I'd like to contribute a little bit, even if it is only (potential) bug 
reporting so far: I tested with scons 2.3.0 and 2.3.1 while compiling 
Fortran sources into a variant directory and discovered that as soon as 
I turn off duplication, it adds another path to the -module option, 
effectively putting the modules back into the source directory. See the 
attached minial example, which produces the following output on my system:

I don't know what the policy is on attachments, so I've pasted all the 
file into the mail (fairly short, though):

$ scons -Q
ifort -o build/bar.o -c -module build -module src src/bar.f90
ifort -o build/foo.o -c -module build -module src src/foo.f90

Note that the first option is what I set, and the second one is added 
automatically as soon as I set "duplicate=0". This overrides the first 
invocation and causes all .mod files to be placed into src/.
Contrarily, if I remove the switch or set "duplicate=1", no extra 
-module directive appears.

I think I see the logic behind this: "If we do an out-of-tree build and 
do not copy the sources, usually the .mod files will be at the same 
place as the source files, so let's add it to the search path".
This would work fine if the order were reversed or turned off in the 
presence of a user-supplied module path (i.e. FORTRANMODDIR variable).

Cheers,
Markus

============================
My example (also available here: 
http://s000.tinyupload.com/index.php?file_id=30075239291299944553)

The directory structure is
.
+-src

| +-SConscript

| +-foo.f90

| +-bar.f90

+-SConstruct
+-build (to be created)


File contents:

SConstruct
--------------------------------------------------------------
import os
env = Environment(ENV = os.environ, tools = ['default', 'ifort'])
env.Replace(
     FORTRANMODDIR = '#build'
)
Export('env')
SConscript('src/SConscript', variant_dir='#build', duplicate=0)
---------------------------------------------------------------

SConscript
--------------------------------------------------------------
Import('env')
env.Program('foo', Glob('*.f90'))
--------------------------------------------------------------

foo.f90
--------------------------------------------------------------
program foo
USE bar_mod
     integer :: i
     i = bar_func(5)
     print*, 'this is at test:', i
end program
--------------------------------------------------------------

bar.f90
--------------------------------------------------------------
module bar_mod
   contains
      function bar_func(x)
         integer :: x, bar_func
         bar_func = 2*x
      end function bar_func
end module
--------------------------------------------------------------