Coin tried to prepend {{.Env.PYTHON3_PATH}}/bin: to PATH on Linux and macOS but there is no PYTHON3_PATH env var set in Linux's provisioning, which accidentally ended up prepending /bin to PATH. This causes issues in CMake where each directory in PATH is used as a potential CMAKE_PREFIX_PATH value (with the /bin stripped), changing the order of prefixes where packages are searched for. In particular, when cross-compiling, this would lead to looking for packages under the '/' prefix before the '/usr' prefix, which can cause issues if /lib is a symlink to /usr/lib, because include paths won't be resolved correctly anymore (different depth of directories). Make sure to prepend {{.Env.PYTHON3_PATH}}/bin: to PATH only on macOS and skip it on Linux hosts. Amends 4af4b4c23551b68d4b207c47054af21ec64e76bd Pick-to: 6.2 Task-number: PYSIDE-802 Change-Id: Ia8a59d501f95733376f8538ba599e963dfb88506 Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io> Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>