Linux build fails

[felixdollack]

Simply running flutter run -v leads to the following error:

[        ] FAILED: CMakeFiles/install.util 
[        ] cd /home/user/Documents/MyApp/build/linux/x64/debug &&
/home/user/development-tools/cmake-3.26.0-linux-x86_64/bin/cmake -P cmake_install.cmake
[        ] ninja: build stopped: subcommand failed.
[        ] CMake Error at plugins/serious_python_linux/cmake_install.cmake:61 (file):
[        ]   file COPY cannot find "///sys/kernel/mm/page_idle/bitmap": Permission
[        ]   denied.
[        ] Call Stack (most recent call first):
[        ]   cmake_install.cmake:272 (include)
[   +4 ms] Building Linux application... (completed in 5.1s)
[        ] Error: Build process failed

Output of flutter doctor:

Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel stable, 3.29.2, on Ubuntu 20.04.6 LTS 5.15.0-139-generic, locale en_US.UTF-8)
[✓] Android toolchain - develop for Android devices (Android SDK version 33.0.2)
[✓] Chrome - develop for the web
[✓] Linux toolchain - develop for Linux desktop
[✓] Android Studio (version 2022.1)
[✓] VS Code (version 1.105.1)
[✓] Connected device (2 available)
[✓] Network resources

• No issues found!

[ndonkoHenri]

That path is the Linux plugin's site-packages install step. Before v3.0.0 it ran file(COPY "$ENV{SERIOUS_PYTHON_SITE_PACKAGES}/" ...) unconditionally — with the variable unset that expands to /, so CMake tried to copy your entire root filesystem and stopped at the first thing it couldn't read under /sys.

Fixed in 3.0.0: the block is now behind if(DEFINED ENV{SERIOUS_PYTHON_SITE_PACKAGES} AND EXISTS ...) (src/serious_python_linux/linux/CMakeLists.txt:180), and 4.0.0 added the same guard for SERIOUS_PYTHON_APP. A bare flutter run with no packaging step now just skips it.