[PATCH 4.20 121/183] isdn: avm: Fix string plus integer warning from Clang

From: Greg Kroah-Hartman
Date: Mon Feb 25 2019 - 16:41:09 EST


4.20-stable review patch. If anyone has any objections, please let me know.

------------------

[ Upstream commit 7afa81c55fca0cad589722cb4bce698b4803b0e1 ]

A recent commit in Clang expanded the -Wstring-plus-int warning, showing
some odd behavior in this file.

drivers/isdn/hardware/avm/b1.c:426:30: warning: adding 'int' to a string does not append to the string [-Wstring-plus-int]
cinfo->version[j] = "\0\0" + 1;
~~~~~~~^~~
drivers/isdn/hardware/avm/b1.c:426:30: note: use array indexing to silence this warning
cinfo->version[j] = "\0\0" + 1;
^
& [ ]
1 warning generated.

This is equivalent to just "\0". Nick pointed out that it is smarter to
use "" instead of "\0" because "" is used elsewhere in the kernel and
can be deduplicated at the linking stage.

Link: https://github.com/ClangBuiltLinux/linux/issues/309
Suggested-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/isdn/hardware/avm/b1.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/isdn/hardware/avm/b1.c b/drivers/isdn/hardware/avm/b1.c
index 4ac378e489023..40ca1e8fa09fc 100644
--- a/drivers/isdn/hardware/avm/b1.c
+++ b/drivers/isdn/hardware/avm/b1.c
@@ -423,7 +423,7 @@ void b1_parse_version(avmctrl_info *cinfo)
int i, j;

for (j = 0; j < AVM_MAXVERSION; j++)
- cinfo->version[j] = "\0\0" + 1;
+ cinfo->version[j] = "";
for (i = 0, j = 0;
j < AVM_MAXVERSION && i < cinfo->versionlen;
j++, i += cinfo->versionbuf[i] + 1)
--
2.19.1