asm-generic: Fix local variable shadow in __set_fixmap_offset

Currently __set_fixmap_offset is a macro function which has a local
variable called 'addr'. If a caller passes a 'phys' parameter which is
derived from a variable also called 'addr', the local variable will
shadow this, and the compiler will complain about the use of an
uninitialized variable. To avoid the issue with namespace clashes,
'addr' is prefixed with a liberal sprinkling of underscores.

Turning __set_fixmap_offset into a static inline breaks the build for
several architectures. Fixing this properly requires updates to a number
of architectures to make them agree on the prototype of __set_fixmap (it
could be done as a subsequent patch series).

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
[catalin.marinas@arm.com: squashed the original function patch and macro fixup]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 3694bd76781b76c4f8d2ecd85018feeb1609f0e5)
Signed-off-by: Alex Shi <alex.shi@linaro.org>

diff --git a/include/asm-generic/fixmap.h b/include/asm-generic/fixmap.h
index 1cbb8338edf391bd83c4d1b0bc0dff2cbbe56e75..827e4d3bbc7a46ef59222651a8020234addc82cb 100644 (file)
--- a/include/asm-generic/fixmap.h
+++ b/include/asm-generic/fixmap.h
@@ -70,12 +70,12 @@ static inline unsigned long virt_to_fix(const unsigned long vaddr)
 #endif
 
 /* Return a pointer with offset calculated */
-#define __set_fixmap_offset(idx, phys, flags)                \
-({                                                           \
-       unsigned long addr;                                   \
-       __set_fixmap(idx, phys, flags);                       \
-       addr = fix_to_virt(idx) + ((phys) & (PAGE_SIZE - 1)); \
-       addr;                                                 \
+#define __set_fixmap_offset(idx, phys, flags)                          \
+({                                                                     \
+       unsigned long ________addr;                                     \
+       __set_fixmap(idx, phys, flags);                                 \
+       ________addr = fix_to_virt(idx) + ((phys) & (PAGE_SIZE - 1));   \
+       ________addr;                                                   \
 })
 
 #define set_fixmap_offset(idx, phys) \