[PATCH 08/12] s390: syscall_wrapper: avoid clang warning

Arnd Bergmann
2019-04-08T21:26:21Z

Building system calls with clang results in a warning
about an alias from a global function to a static one:

../fs/namei.c:3847:1: warning: unused function '__se_sys_mkdirat' [-Wunused-function]
SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode)
^
../include/linux/syscalls.h:219:36: note: expanded from macro 'SYSCALL_DEFINE3'
#define SYSCALL_DEFINE3(name, ...) SYSCALL_DEFINEx(3, _##name, __VA_ARGS__)
^
../include/linux/syscalls.h:228:2: note: expanded from macro 'SYSCALL_DEFINEx'
__SYSCALL_DEFINEx(x, sname, __VA_ARGS__)
^
../arch/s390/include/asm/syscall_wrapper.h:126:18: note: expanded from macro '__SYSCALL_DEFINEx'
asmlinkage long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \
^
<scratch space>:31:1: note: expanded from here
__se_sys_mkdirat
^

The only reference to the static __se_sys_mkdirat() here is the alias, but
this only gets evaluated later. Making this function global as well avoids
the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
I considered opening a bug report for llvm here, but I suspect the
behavior is intentional, so I'm just fixing it here. Let me know if
you disagree.
---
arch/s390/include/asm/syscall_wrapper.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/s390/include/asm/syscall_wrapper.h b/arch/s390/include/asm/syscall_wrapper.h
index 5596c5c625d2..3c3d6fe8e2f0 100644
--- a/arch/s390/include/asm/syscall_wrapper.h
+++ b/arch/s390/include/asm/syscall_wrapper.h
@@ -119,8 +119,8 @@
"Type aliasing is used to sanitize syscall arguments");\
asmlinkage long __s390x_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) \
__attribute__((alias(__stringify(__se_sys##name)))); \
- ALLOW_ERROR_INJECTION(__s390x_sys##name, ERRNO); \
- static long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
+ ALLOW_ERROR_INJECTION(__s390x_sys##name, ERRNO); \
+ long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
static inline long __do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)); \
__S390_SYS_STUBx(x, name, __VA_ARGS__) \
asmlinkage long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \
--
2.20.0