This plugin has no impact on the resulting binary, is disabled under COMPILE_TEST, and is not enabled on any builds I'm aware of. Additionally, given the clarified purpose of GCC plugins in the kernel, remove cyc_complexity. Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx> Cc: Michal Marek <michal.lkml@xxxxxxxxxxx> Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Cc: Jonathan Corbet <corbet@xxxxxxx> Cc: linux-hardening@xxxxxxxxxxxxxxx Cc: linux-kbuild@xxxxxxxxxxxxxxx Cc: linux-doc@xxxxxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- Documentation/kbuild/gcc-plugins.rst | 2 - scripts/Makefile.gcc-plugins | 2 - scripts/gcc-plugins/Kconfig | 16 ----- scripts/gcc-plugins/cyc_complexity_plugin.c | 69 --------------------- 4 files changed, 89 deletions(-) delete mode 100644 scripts/gcc-plugins/cyc_complexity_plugin.c diff --git a/Documentation/kbuild/gcc-plugins.rst b/Documentation/kbuild/gcc-plugins.rst index 4b28c7a4032f..0ba76719f1b9 100644 --- a/Documentation/kbuild/gcc-plugins.rst +++ b/Documentation/kbuild/gcc-plugins.rst @@ -96,7 +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 ... @@ -115,4 +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. diff --git a/scripts/Makefile.gcc-plugins b/scripts/Makefile.gcc-plugins index 952e46876329..6583ecf2e674 100644 --- a/scripts/Makefile.gcc-plugins +++ b/scripts/Makefile.gcc-plugins @@ -1,7 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 -gcc-plugin-$(CONFIG_GCC_PLUGIN_CYC_COMPLEXITY) += cyc_complexity_plugin.so - gcc-plugin-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) += latent_entropy_plugin.so gcc-plugin-cflags-$(CONFIG_GCC_PLUGIN_LATENT_ENTROPY) \ += -DLATENT_ENTROPY_PLUGIN diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig index 3f5d3580ec06..821a725a7f5c 100644 --- a/scripts/gcc-plugins/Kconfig +++ b/scripts/gcc-plugins/Kconfig @@ -19,22 +19,6 @@ menuconfig GCC_PLUGINS if GCC_PLUGINS -config GCC_PLUGIN_CYC_COMPLEXITY - bool "Compute the cyclomatic complexity of a function" if EXPERT - depends on !COMPILE_TEST # too noisy - help - The complexity M of a function's control flow graph is defined as: - M = E - N + 2P - where - - E = the number of edges - N = the number of nodes - P = the number of connected components (exit nodes). - - Enabling this plugin reports the complexity to stderr during the - build. It mainly serves as a simple example of how to create a - gcc plugin for the kernel. - config GCC_PLUGIN_SANCOV bool # Plugin can be removed once the kernel only supports GCC 6.1.0+ diff --git a/scripts/gcc-plugins/cyc_complexity_plugin.c b/scripts/gcc-plugins/cyc_complexity_plugin.c deleted file mode 100644 index 73124c2b3edd..000000000000 --- a/scripts/gcc-plugins/cyc_complexity_plugin.c +++ /dev/null @@ -1,69 +0,0 @@ -/* - * Copyright 2011-2016 by Emese Revfy <re.emese@xxxxxxxxx> - * Licensed under the GPL v2, or (at your option) v3 - * - * Homepage: - * https://github.com/ephox-gcc-plugins/cyclomatic_complexity - * - * https://en.wikipedia.org/wiki/Cyclomatic_complexity - * The complexity M is then defined as: - * M = E - N + 2P - * where - * - * E = the number of edges of the graph - * N = the number of nodes of the graph - * P = the number of connected components (exit nodes). - * - * Usage (4.5 - 5): - * $ make clean; make run - */ - -#include "gcc-common.h" - -__visible int plugin_is_GPL_compatible; - -static struct plugin_info cyc_complexity_plugin_info = { - .version = "20160225", - .help = "Cyclomatic Complexity\n", -}; - -static unsigned int cyc_complexity_execute(void) -{ - int complexity; - expanded_location xloc; - - /* M = E - N + 2P */ - complexity = n_edges_for_fn(cfun) - n_basic_blocks_for_fn(cfun) + 2; - - xloc = expand_location(DECL_SOURCE_LOCATION(current_function_decl)); - fprintf(stderr, "Cyclomatic Complexity %d %s:%s\n", complexity, - xloc.file, DECL_NAME_POINTER(current_function_decl)); - - return 0; -} - -#define PASS_NAME cyc_complexity - -#define NO_GATE -#define TODO_FLAGS_FINISH TODO_dump_func - -#include "gcc-generate-gimple-pass.h" - -__visible int plugin_init(struct plugin_name_args *plugin_info, struct plugin_gcc_version *version) -{ - const char * const plugin_name = plugin_info->base_name; - - PASS_INFO(cyc_complexity, "ssa", 1, PASS_POS_INSERT_AFTER); - - if (!plugin_default_version_check(version, &gcc_version)) { - error(G_("incompatible gcc/plugin versions")); - return 1; - } - - register_callback(plugin_name, PLUGIN_INFO, NULL, - &cyc_complexity_plugin_info); - register_callback(plugin_name, PLUGIN_PASS_MANAGER_SETUP, NULL, - &cyc_complexity_pass_info); - - return 0; -} -- 2.30.2
