[NET]: Elminate spurious print_mac() calls.
Patrick McHardy notes that print_mac() can get invoked
even if the result it unused (f.e. as an argument to
pr_debug() when DEBUG is not defined).
Mark this function as "__pure" to eliminate this problem.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/if_ether.h b/include/linux/if_ether.h
index 7a1e011..42dc6a3 100644
--- a/include/linux/if_ether.h
+++ b/include/linux/if_ether.h
@@ -129,7 +129,7 @@
/*
* Display a 6 byte device address (MAC) in a readable format.
*/
-extern char *print_mac(char *buf, const unsigned char *addr);
+extern __pure char *print_mac(char *buf, const unsigned char *addr);
#define MAC_BUF_SIZE 18
#define DECLARE_MAC_BUF(var) char var[MAC_BUF_SIZE] __maybe_unused