From fb092eb63d3aba5b876a51cbe743c1c8a8b37d5b Mon Sep 17 00:00:00 2001
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Fri, 31 May 2019 22:30:09 -0700
Subject: [PATCH] arch/arm/boot/compressed/decompress.c: fix build error due to
 lz4 changes

  include/linux/cpumask.h: In function 'cpumask_parse':
  include/linux/cpumask.h:636:21: error: implicit declaration of function 'strchrnul'; did you mean 'strchr'? [-Werror=implicit-function-declaration]

Because arch/arm/boot/compressed/decompress.c does

#define _LINUX_STRING_H_

preventing linux/string.h from providing strchrnul.  It also #includes
asm/string.h, which for arm has a declaration of strchr(), explaining why
this didn't use to fail.

Link: http://lkml.kernel.org/r/20190528115346.f5a7kn3hdnuf5rts@linutronix.de
Fixes: 3713a4e1fdb8d ("include/linux/cpumask.h: fix double string traverse in cpumask_parse")
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Yury Norov <ynorov@marvell.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 arch/arm/boot/compressed/decompress.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/boot/compressed/decompress.c b/arch/arm/boot/compressed/decompress.c
index c16c1829a5e4..aa075d8372ea 100644
--- a/arch/arm/boot/compressed/decompress.c
+++ b/arch/arm/boot/compressed/decompress.c
@@ -32,6 +32,7 @@
 extern char * strstr(const char * s1, const char *s2);
 extern size_t strlen(const char *s);
 extern int memcmp(const void *cs, const void *ct, size_t count);
+extern char * strchrnul(const char *, int);
 
 #ifdef CONFIG_KERNEL_GZIP
 #include "../../../../lib/decompress_inflate.c"