diff options
Diffstat (limited to 'Documentation/kbuild/gcc-plugins.rst')
-rw-r--r-- | Documentation/kbuild/gcc-plugins.rst | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/Documentation/kbuild/gcc-plugins.rst b/Documentation/kbuild/gcc-plugins.rst index 3349966f213d..0ba76719f1b9 100644 --- a/Documentation/kbuild/gcc-plugins.rst +++ b/Documentation/kbuild/gcc-plugins.rst @@ -32,6 +32,32 @@ This infrastructure was ported from grsecurity [6]_ and PaX [7]_. .. [7] https://pax.grsecurity.net/ +Purpose +======= + +GCC plugins are designed to provide a place to experiment with potential +compiler features that are neither in GCC nor Clang upstream. Once +their utility is proven, the goal is to upstream the feature into GCC +(and Clang), and then to finally remove them from the kernel once the +feature is available in all supported versions of GCC. + +Specifically, new plugins should implement only features that have no +upstream compiler support (in either GCC or Clang). + +When a feature exists in Clang but not GCC, effort should be made to +bring the feature to upstream GCC (rather than just as a kernel-specific +GCC plugin), so the entire ecosystem can benefit from it. + +Similarly, even if a feature provided by a GCC plugin does *not* exist +in Clang, but the feature is proven to be useful, effort should be spent +to upstream the feature to GCC (and Clang). + +After a feature is available in upstream GCC, the plugin will be made +unbuildable for the corresponding GCC version (and later). Once all +kernel-supported versions of GCC provide the feature, the plugin will +be removed from the kernel. + + Files ===== @@ -70,7 +96,6 @@ Enable the GCC plugin infrastructure and some plugin(s) you want to use in the kernel config:: CONFIG_GCC_PLUGINS=y - CONFIG_GCC_PLUGIN_CYC_COMPLEXITY=y CONFIG_GCC_PLUGIN_LATENT_ENTROPY=y ... @@ -89,4 +114,3 @@ The GCC plugins are in scripts/gcc-plugins/. You need to put plugin source files right under scripts/gcc-plugins/. Creating subdirectories is not supported. It must be added to scripts/gcc-plugins/Makefile, scripts/Makefile.gcc-plugins and a relevant Kconfig file. -See the cyc_complexity_plugin.c (CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) GCC plugin. |