This is a note to let you know that I've just added the patch titled tools include: Do not use poison with C++ to the 4.9-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: tools-include-do-not-use-poison-with-c.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Wed Dec 6 17:39:55 CET 2017 From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Date: Thu, 21 Sep 2017 12:12:17 -0300 Subject: tools include: Do not use poison with C++ From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> [ Upstream commit 6ae8eefc6c8fe050f057781b70a83262eb0a61ee ] LIST_POISON[12] are used to initialize list_head and hlist_node pointers, and do void pointer arithmetic, which C++ doesn't like, so, to avoid drifting from the kernel by introducing some HLIST_POISON to do away with void pointer math, just make those poisoned pointers be NULL when building it with a C++ compiler. Noticed with: $ make LLVM_CONFIG=/usr/bin/llvm-config-3.9 LIBCLANGLLVM=1 CXX util/c++/clang.o CXX util/c++/clang-test.o In file included from /home/lizj/linux/tools/include/linux/list.h:5:0, from /home/lizj/linux/tools/perf/util/namespaces.h:13, from /home/lizj/linux/tools/perf/util/util.h:15, from /home/lizj/linux/tools/perf/util/util-cxx.h:20, from util/c++/clang-c.h:5, from util/c++/clang-test.cpp:2: /home/lizj/linux/tools/include/linux/list.h: In function ‘void list_del(list_head*)’: /home/lizj/linux/tools/include/linux/poison.h:14:31: error: pointer of type ‘void *’ used in arithmetic [-Werror=pointer-arith] # define POISON_POINTER_DELTA 0 ^ /home/lizj/linux/tools/include/linux/poison.h:22:41: note: in expansion of macro ‘POISON_POINTER_DELTA’ #define LIST_POISON1 ((void *) 0x100 + POISON_POINTER_DELTA) ^ /home/lizj/linux/tools/include/linux/list.h:107:16: note: in expansion of macro ‘LIST_POISON1’ entry->next = LIST_POISON1; ^ In file included from /home/lizj/linux/tools/perf/util/namespaces.h:13:0, from /home/lizj/linux/tools/perf/util/util.h:15, from /home/lizj/linux/tools/perf/util/util-cxx.h:20, from util/c++/clang-c.h:5, from util/c++/clang-test.cpp:2: /home/lizj/linux/tools/include/linux/list.h:107:14: error: invalid conversion from ‘void*’ to ‘list_head*’ [-fpermissive] Reported-by: Li Zhijian <lizhijian@xxxxxxxxxxxxxx> Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: David Ahern <dsahern@xxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Philip Li <philip.li@xxxxxxxxx> Cc: Wang Nan <wangnan0@xxxxxxxxxx> Link: http://lkml.kernel.org/n/tip-m5ei2o0mjshucbr28baf5lqz@xxxxxxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/include/linux/poison.h | 5 +++++ 1 file changed, 5 insertions(+) --- a/tools/include/linux/poison.h +++ b/tools/include/linux/poison.h @@ -14,6 +14,10 @@ # define POISON_POINTER_DELTA 0 #endif +#ifdef __cplusplus +#define LIST_POISON1 NULL +#define LIST_POISON2 NULL +#else /* * These are non-NULL pointers that will result in page faults * under normal circumstances, used to verify that nobody uses @@ -21,6 +25,7 @@ */ #define LIST_POISON1 ((void *) 0x100 + POISON_POINTER_DELTA) #define LIST_POISON2 ((void *) 0x200 + POISON_POINTER_DELTA) +#endif /********** include/linux/timer.h **********/ /* Patches currently in stable-queue which might be from acme@xxxxxxxxxx are queue-4.9/perf-test-attr-fix-ignored-test-case-result.patch queue-4.9/perf-x86-intel-account-interrupts-for-pebs-errors.patch queue-4.9/tools-include-do-not-use-poison-with-c.patch