[patch 074/115] asm-generic/bug.h: declare struct pt_regs; before function prototype

[patch 074/115] asm-generic/bug.h: declare struct pt_regs; before function prototype

[akpm]

From: Ian Abbott <abbotti@mev.co.uk>
Subject: asm-generic/bug.h: declare struct pt_regs; before function prototype

This series of patches splits BUILD_BUG related macros out of
"include/linux/bug.h" into new file "include/linux/build_bug.h" (patch 5),
and changes the pointer type checking in the `container_of()` macro to
deal with pointers of array type better (patch 6).  Patches 1 to 4 are
prerequisites.

Patches 2, 3, 4, and 5 have been inserted since the previous version of
this patch series.  Patch 6 here corresponds to v3 and v4's patch 2.

Patch 1 was a prerequisite in v3 of this series to avoid a lot of warnings
when <linux/bug.h> was included by <linux/kernel.h>.  That is no longer
relevant for v5 of the series, but I left it in because it was acked by a
Arnd Bergmann and Michal Nazarewicz.

Patches 2, 3, and 4 are some checkpatch clean-ups on "include/linux/bug.h"
before splitting out the BUILD_BUG stuff in patch 5.

Patch 5 splits the BUILD_BUG related macros out of "include/linux/bug.h"
into new file "include/linux/build_bug.h" because including <linux/bug.h>
in "include/linux/kernel.h" would result in build failures due to circular
dependencies.

Patch 6 changes the pointer type checking by `container_of()` to avoid
some incompatible pointer warnings when the dereferenced pointer has array
type.

1) asm-generic/bug.h: declare struct pt_regs; before function prototype
2) linux/bug.h: correct formatting of block comment
3) linux/bug.h: correct "(foo*)" should be "(foo *)"
4) linux/bug.h: correct "space required before that '-'"
5) bug: split BUILD_BUG stuff out into <linux/build_bug.h>
6) kernel.h: handle pointers to arrays better in container_of()


This patch (of 6):

The declaration of `__warn()` has `struct pt_regs *regs` as one of its
parameters.  This can result in compiler warnings if `struct regs` is not
already declared.  Add an empty declaration of `struct pt_regs` to avoid
the warnings.

Link: http://lkml.kernel.org/r/20170525120316.24473-2-abbotti@mev.co.uk
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/asm-generic/bug.h |    1 +
 1 file changed, 1 insertion(+)

diff -puN include/asm-generic/bug.h~asm-generic-bugh-declare-struct-pt_regs-before-function-prototype include/asm-generic/bug.h
--- a/include/asm-generic/bug.h~asm-generic-bugh-declare-struct-pt_regs-before-function-prototype
+++ a/include/asm-generic/bug.h
@@ -97,6 +97,7 @@ extern void warn_slowpath_null(const cha
 
 /* used internally by panic.c */
 struct warn_args;
+struct pt_regs;
 
 void __warn(const char *file, int line, void *caller, unsigned taint,
 	    struct pt_regs *regs, struct warn_args *args);
_