From: Li Chen <[email protected]> Hello,
This patch series introduces a new GCC plugin called cleanup_plugin that warns developers about problematic patterns when using variables with __attribute__((cleanup(...))). The plugin addresses concerns documented in include/linux/cleanup.h regarding resource leaks and interdependency issues. The cleanup attribute helpers (__free, DEFINE_FREE, etc.) are designed to automatically clean up resources when variables go out of scope, following LIFO (last in first out) ordering. However, certain patterns can lead to subtle bugs: 1. Uninitialized cleanup variables: Variables declared with cleanup attributes but not initialized can cause issues when cleanup functions are called on undefined values. 2. NULL-initialized cleanup variables: The "__free(...) = NULL" pattern at function top can cause interdependency problems, especially when combined with guards or multiple cleanup variables, as the cleanup may run in unexpected contexts. The plugin detects both of these problematic patterns and provides clear warnings to developers, helping prevent incorrect cleanup ordering. Importantly, the plugin's warnings are not converted to errors by -Werror, allowing builds to continue while still alerting developers to potential issues. The plugin is enabled by default as it provides valuable compile-time feedback without impacting build performance. Li Chen (2): gcc-plugins: add cleanup_plugin for uninitialized cleanup detection gcc-plugins: cleanup_plugin: detect NULL init scripts/Makefile.gcc-plugins | 1 + scripts/gcc-plugins/Kconfig | 6 + scripts/gcc-plugins/cleanup_plugin.c | 204 +++++++++++++++++++++++++++ 3 files changed, 211 insertions(+) create mode 100644 scripts/gcc-plugins/cleanup_plugin.c -- 2.51.0
