[cmake-developers] CMake crashes on removing INCLUDE_DIRECTORIES property

[Brad King]

Steve,

Since this commit:

 http://cmake.org/gitweb?p=cmake.git;a=commitdiff;h=18a3195a

CMake crashes on the code

 set_property(DIRECTORY PROPERTY INCLUDE_DIRECTORIES)

because code like

 this->IncludeDirectoriesEntries.push_back(
                        cmValueWithOrigin(value, lfbt));

assumes that "value" is non-null.  However, the internal value
used when *removing* a property is exactly null (0).  It is not
just a matter of tolerating a null value.  The value indicates
that the property should be removed altogether.

Please fix the include directory vector representation to
support removing the property altogether and add a test case.
We'll need to get this in before 2.8.11 final.

Thanks,
-Brad