This is a note to let you know that I've just added the patch titled
gcc-plugins: drop -std=gnu++11 to fix GCC 13 build
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
gcc-plugins-drop-std-gnu-11-to-fix-gcc-13-build.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit cc2fda9e23d97a1b2b1b64c31168f91c65feecd7
Author: Sam James <sam@xxxxxxxxxx>
Date: Wed Feb 1 23:00:09 2023 +0000
gcc-plugins: drop -std=gnu++11 to fix GCC 13 build
[ Upstream commit 5a6b64adc18d9adfb497a529ff004d59b6df151f ]
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 <sam@xxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230201230009.2252783-1-sam@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile
index b34d11e226366..320afd3cf8e82 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
