From 5a6b64adc18d9adfb497a529ff004d59b6df151f Mon Sep 17 00:00:00 2001 From: Sam James Date: Wed, 1 Feb 2023 23:00:09 +0000 Subject: [PATCH] gcc-plugins: drop -std=gnu++11 to fix GCC 13 build The latest GCC 13 snapshot (13.0.1 20230129) gives the following: ``` cc1: error: cannot load plugin ./scripts/gcc-plugins/randomize_layout_plugin.so :./scripts/gcc-plugins/randomize_layout_plugin.so: undefined symbol: tree_code_type ``` This ends up being because of https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;h=b0241ce6e37031 upstream in GCC which changes the visibility of some types used by the kernel's plugin infrastructure like tree_code_type. After discussion with the GCC folks, we found that the kernel needs to be building plugins with the same flags used to build GCC - and GCC defaults to gnu++17 right now. The minimum GCC version needed to build the kernel is GCC 5.1 and GCC 5.1 already defaults to gnu++14 anyway, so just drop the flag, as all GCCs that could be used to build GCC already default to an acceptable version which was >= the version we forced via flags until now. Bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108634 Signed-off-by: Sam James Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20230201230009.2252783-1-sam@gentoo.org --- scripts/gcc-plugins/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile index b34d11e22636..320afd3cf8e8 100644 --- a/scripts/gcc-plugins/Makefile +++ b/scripts/gcc-plugins/Makefile @@ -29,7 +29,7 @@ GCC_PLUGINS_DIR = $(shell $(CC) -print-file-name=plugin) plugin_cxxflags = -Wp,-MMD,$(depfile) $(KBUILD_HOSTCXXFLAGS) -fPIC \ -include $(srctree)/include/linux/compiler-version.h \ -DPLUGIN_VERSION=$(call stringify,$(KERNELVERSION)) \ - -I $(GCC_PLUGINS_DIR)/include -I $(obj) -std=gnu++11 \ + -I $(GCC_PLUGINS_DIR)/include -I $(obj) \ -fno-rtti -fno-exceptions -fasynchronous-unwind-tables \ -ggdb -Wno-narrowing -Wno-unused-variable \ -Wno-format-diag