Okay, I see why you're having the issue. Your library flag in the libtwo project is:
The compiler, with the -static flag set, is looking for a file named libone.a. Apparently, if you remove the -static flag, it will instead use libone.dll if anything, which is actually a bit of a surprise to me.
Anyway, the ideal solution is to generate an import library while building the DLL. Simply Fortran probably should do this by default, but it currently doesn't. We ideally want to create a file libone.dll.a that will merely contain the declaration of exported symbols in libone.dll. To do so, load your libone project and open the Project Options dialog. In the Linker text field under Project Flags, add the following:
That first part is "capital double-U el," and it instructs gfortran to pass along the flag after the comma to the linker directly. Now clean and rebuild your libone project. If you navigate to that directory, you should now see a libone.dll and libone.dll.a.
Next, open your libtwo project. Open the Project Options dialog and change your library flag from:
Clean and rebuild your project, and everything should work fine.
The above method is actually how most GNU-compiled DLLs are linked to under Windows. The GTK+ project is a good example. In their lib directory are an assortment of "libgtk-2.0.dll.a" and similar files.
The above should fix your issue, although it is not necessarily ideal. I think Simply Fortran should allow for two things:
1. Import libraries should be created by default when building DLLs
2. Users should be able to optionally disable static linking
Let me know if this solution works out. It's good to hear someone is using Simply Fortran under WINE. A reasonable amount of Simply Fortran's development takes place under WINE using Simply Fortran itself as the IDE. The only real issue I've come across is the Start screen not loading properly. If you do see any other problems under WINE, please don't hesitate to post them.