The checkDuplicateHeaders function in Distribution.Simple.Configure removes header files from the source directory when a header with the same name exists in both the build directory and the source directory.

This behavior was introduced in commit 3a9830b to resolve header precedence issues, as C compilers prefer relative includes over -I search paths. The workaround uses removeFile on source directory files, which is destructive and should not happen during a build process.

While the current implementation does not follow symlinks explicitly, the deletion of source files outside of the project during a build operation is possible on Microsoft Windows.