Commit-ID: 6ae8eefc6c8fe050f057781b70a83262eb0a61ee
Gitweb: http://git.kernel.org/tip/6ae8eefc6c8fe050f057781b70a83262eb0a61ee
Author: Arnaldo Carvalho de Melo <[email protected]>
AuthorDate: Thu, 21 Sep 2017 12:12:17 -0300
Committer: Arnaldo Carvalho de Melo <[email protected]>
CommitDate: Thu, 21 Sep 2017 13:13:00 -0300
tools include: Do not use poison with C++
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 <[email protected]>
Cc: Adrian Hunter <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: David Ahern <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Philip Li <[email protected]>
Cc: Wang Nan <[email protected]>
Link: http://lkml.kernel.org/n/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
tools/include/linux/poison.h | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/tools/include/linux/poison.h b/tools/include/linux/poison.h
index 51334ed..f306a76 100644
--- 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 **********/
/*
