A new SCons release, 4.5.2, is now available on the SCons download page:

    https://scons.org/pages/download.html

Here is a summary of the changes since 4.5.1:

FIXES
-----

-  Fix a problem (#4321) in 4.5.0/4.5.1 where ParseConfig could cause an
   exception in MergeFlags when the result would be to add preprocessor
   defines to existing CPPDEFINES. The following code illustrates the
   circumstances that could trigger this:
      env=Environment(CPPDEFINES=['a'])
      env.Append(CPPDEFINES=['b'])
      env.MergeFlags({'CPPDEFINES': 'c'})

PACKAGING
---------

- Remove the redundant `wheel` dependency from `pyproject.toml`,
  as it is added automatically by the setuptools PEP517 backend.


Thanks to the following contributors listed below for their contributions to this release.
==========================================================================================
.. code-block:: text

    git shortlog --no-merges -ns 4.5.1..HEAD
     3  Mats Wichmann
     2  William Deegan
     1  Michał Górny
