stacktrace: add forward-declaration struct task_struct

This is needed if the header is to be free-standing.

Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/stacktrace.h b/include/linux/stacktrace.h
index 551f6c7d5044..51efbef38fb0 100644
--- a/include/linux/stacktrace.h
+++ b/include/linux/stacktrace.h
@@ -4,6 +4,8 @@
 struct task_struct;
 
 #ifdef CONFIG_STACKTRACE
+struct task_struct;
+
 struct stack_trace {
         unsigned int nr_entries, max_entries;
         unsigned long *entries;