[PATCH v2 3/4] lib/vsprintf.c: Remove SPECIAL handling in pointer()

From: Rasmus Villemoes
Date: Wed Sep 30 2015 - 11:31:16 EST


As a quick

git grep -E '%[ +0#-]*#[ +0#-]*(\*|[0-9]+)?(\.(\*|[0-9]+)?)?p'

shows, nobody uses the # flag with %p. Should one try to do so, one
will be met with

warning: `#' flag used with â%pâ gnu_printf format [-Wformat]

(POSIX and C99 both say "... For other conversion specifiers, the
behavior is undefined.". Obviously, the kernel can choose to define
the behaviour however it wants, but as long as gcc issues that
warning, users are unlikely to show up.)

Since default_width is effectively always 2*sizeof(void*), we can
simplify the prologue of pointer() and save a few instructions.

Signed-off-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
---
v2: reword slightly, refer to POSIX/C99.

lib/vsprintf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 03fa10b4be96..98b0d7be3fb7 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -1457,7 +1457,7 @@ static noinline_for_stack
char *pointer(const char *fmt, char *buf, char *end, void *ptr,
struct printf_spec spec)
{
- int default_width = 2 * sizeof(void *) + (spec.flags & SPECIAL ? 2 : 0);
+ const int default_width = 2 * sizeof(void *);

if (!ptr && *fmt != 'K') {
/*
--
2.1.3

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