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HOOPS Exchange 2019 SP2 U2
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Future Platform Changes
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With *HOOPS Exchange 2020*, Linux and Android platforms will be upgraded:

* **Linux**:

  * Minimum OS version for _CentOS_ upgraded from 6.x to **7**
  * Compiler toolchain version upgraded from GCC 6.5 to **GCC 8**

* **Android**:

  * Compiler toolchain version upgraded from NDK 11c to NDK 19c

.. note::

   This release does not contain this platform change. It is an informational notice for the next major release._

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Behavior regarding empty model files
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HOOPS API will ensure a model file always have at least a root product occurrence:

* When creating a new model file with \ref A3DAsmModelFileCreate, if the provided data doesn't have any product occurrence, a root will be implicitly created.
* Any model file with no root product occurrence is considered inconsistent. When getting a model file using \ref A3DAsmModelFileGet, the function returns `A3D_MODELFILE_INCONSISTENT_EMPTY`.

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Notes about the C++ API
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Along with the 2018 SP1 release, we added a new C++ interface for Exchange and HOOPS Publish.
This API is considered as a pre-release version and may be discontinued in the future in favor of a
smoother experience with already existing APIs we provide.

.. rubric:: Bug fixes

The list of fixed bugs can be found on :doc:`/fixed_bugs`.



