From: Arnd Bergmann <arnd@xxxxxxxx> The arch_get_vdso_data() function is defined separately on each architecture, but only called when CONFIG_TIME_NS is set. If the definition is a global function, this causes a W=1 warning without TIME_NS: arch/x86/entry/vdso/vma.c:35:19: error: no previous prototype for 'arch_get_vdso_data' [-Werror=missing-prototypes] Move the prototype out of the #ifdef block to reliably turn off that warning. Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> --- include/linux/time_namespace.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/linux/time_namespace.h b/include/linux/time_namespace.h index bb9d3f5542f8..03d9c5ac01d1 100644 --- a/include/linux/time_namespace.h +++ b/include/linux/time_namespace.h @@ -44,7 +44,6 @@ struct time_namespace *copy_time_ns(unsigned long flags, struct time_namespace *old_ns); void free_time_ns(struct time_namespace *ns); void timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk); -struct vdso_data *arch_get_vdso_data(void *vvar_page); struct page *find_timens_vvar_page(struct vm_area_struct *vma); static inline void put_time_ns(struct time_namespace *ns) @@ -163,4 +162,6 @@ static inline ktime_t timens_ktime_to_host(clockid_t clockid, ktime_t tim) } #endif +struct vdso_data *arch_get_vdso_data(void *vvar_page); + #endif /* _LINUX_TIMENS_H */ -- 2.39.2