That depends on the Modelica tool used and the licenses of the libraries that the model uses.
OpenModelica has a BSD-license option for the simulation runtime, which imposes no real restrictions (just attribution in documentation if you link to the runtime).

The following is from the OSMC bylaws, which clarifies our position. https://openmodelica.org/images/docs/op … -final.pdf, §1.5:
The ownership, copyright, and possible usage license of source code translated by the OpenModelica Compiler into translated code also holds for the translated code originating from that corresponding source code. [This is a consequence of translated code being considered derivative work of the input source code, and that OpenModelica does not impose additional restrictions on generated code in addition to what holds for the input source code.]

So, if I've correctly understood, if I use openmodelica and my model uses only the modelica standard library, the C code generated from such a model can be distributed with whatever licence I want and, in case, linked to proprietary code.
Is it correct?
Xwang

Pretty much. If it's linked to the runtime, you have BSD 3-clause and OSMC-PL Runtime license to consider, so:
* Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
* Neither the name of the <ORGANIZATION> nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
(Include a copy of BSD 3-clause)

And for OSMC-PL you should:
* A recipient must clearly indicate its chosen usage mode of OSMC-PL, in accompanying documentation and in a text file OSMC-USAGE-MODE.txt, provided with the distribution.

So just include a text saying you use the OSMC-PL BSD 3-clause mode and a copy of the license (for distribution). As well as the copyright notices from the MSL and you should have covered all your bases. Not that I think anyone will mind anyway.

But yes, it can be linked to proprietary code and you may ship it with any license (shareware, commercial, free there should be no problem).

So the OSMC-PL is required? Can the OSMC-GPL be used instead (if I 've understood correctly OSMC-GPL covers the compiler which generally do not extend the licence to the compiled code or at least it is so with the gcc compiler)?

The OSMC-PL runtime license has the option to use OSMC-GPL or OSMC-BSD. (This is only applicable if you link our runtime code with the generated code.)

And to link the 3-clause BSD: http://www.opensource.org/licenses/BSD-3-Clause

Perfect.
So there is no real problem in the above scenario.
Thank you for your help.
Xwang