[PATCH v2 4/5] powerpc: Fix duplicate const clang warning in user access code

[Joel Stanley]

From: Anton Blanchard <anton at samba.org>

This re-applies b91c1e3e7a6f which was reverted in f2ca80905929
d466f6c5cac1 f84ed59a612d (powerpc/sparse: Constify the address pointer
...").

We see a large number of duplicate const errors in the user access
code when building with llvm/clang:

  include/linux/pagemap.h:576:8: warning: duplicate 'const' declaration specifier
      [-Wduplicate-decl-specifier]
        ret = __get_user(c, uaddr);

The problem is we are doing const __typeof__(*(ptr)), which will hit the
warning if ptr is marked const.

Removing const does not seem to have any effect on GCC code generation.

Signed-off-by: Anton Blanchard <anton at samba.org>
Signed-off-by: Joel Stanley <joel at jms.id.au>
---
If we don't want to apply this, other options are suppressing the
warning, or wait for a fix to land in clang
(https://github.com/ClangBuiltLinux/linux/issues/52).
---
 arch/powerpc/include/asm/uaccess.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index bac225bb7f64..15bea9a0f260 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -260,7 +260,7 @@ do {								\
 ({								\
 	long __gu_err;						\
 	__long_type(*(ptr)) __gu_val;				\
-	const __typeof__(*(ptr)) __user *__gu_addr = (ptr);	\
+	__typeof__(*(ptr)) __user *__gu_addr = (ptr);	\
 	__chk_user_ptr(ptr);					\
 	if (!is_kernel_addr((unsigned long)__gu_addr))		\
 		might_fault();					\
@@ -274,7 +274,7 @@ do {								\
 ({									\
 	long __gu_err = -EFAULT;					\
 	__long_type(*(ptr)) __gu_val = 0;				\
-	const __typeof__(*(ptr)) __user *__gu_addr = (ptr);		\
+	__typeof__(*(ptr)) __user *__gu_addr = (ptr);		\
 	might_fault();							\
 	if (access_ok(VERIFY_READ, __gu_addr, (size))) {		\
 		barrier_nospec();					\
@@ -288,7 +288,7 @@ do {								\
 ({								\
 	long __gu_err;						\
 	__long_type(*(ptr)) __gu_val;				\
-	const __typeof__(*(ptr)) __user *__gu_addr = (ptr);	\
+	__typeof__(*(ptr)) __user *__gu_addr = (ptr);	\
 	__chk_user_ptr(ptr);					\
 	barrier_nospec();					\
 	__get_user_size(__gu_val, __gu_addr, (size), __gu_err);	\
-- 
2.17.1