lkml.org 
[lkml]   [2017]   [Sep]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] drm/gma500: initialize gma_clock_t structures
Date
The two functions pass a partially initialized structure back to the
caller after a memset() on the destination.

This is not entirely well-defined, most compilers are sensible enough
to either keep the zero-initialization for the uninitialized members,
but gcc-4.4 does not, and it warns about this:

drivers/gpu/drm/gma500/oaktrail_crtc.c: In function 'mrst_sdvo_find_best_pll':
drivers/gpu/drm/gma500/oaktrail_crtc.c:175: warning: 'clock.vco' may be used uninitialized in this function
drivers/gpu/drm/gma500/oaktrail_crtc.c:175: warning: 'clock.dot' may be used uninitialized in this function
drivers/gpu/drm/gma500/oaktrail_crtc.c:175: warning: 'clock.p2' may be used uninitialized in this function
drivers/gpu/drm/gma500/oaktrail_crtc.c:175: warning: 'clock.m2' may be used uninitialized in this function
drivers/gpu/drm/gma500/oaktrail_crtc.c:175: warning: 'clock.m1' may be used uninitialized in this function
drivers/gpu/drm/gma500/oaktrail_crtc.c: In function 'mrst_lvds_find_best_pll':
drivers/gpu/drm/gma500/oaktrail_crtc.c:208: warning: 'clock.p' may be used uninitialized in this function
drivers/gpu/drm/gma500/oaktrail_crtc.c:208: warning: 'clock.vco' may be used uninitialized in this function
drivers/gpu/drm/gma500/oaktrail_crtc.c:208: warning: 'clock.p2' may be used uninitialized in this function
drivers/gpu/drm/gma500/oaktrail_crtc.c:208: warning: 'clock.m2' may be used uninitialized in this function
drivers/gpu/drm/gma500/oaktrail_crtc.c:208: warning: 'clock.m1' may be used uninitialized in this function
drivers/gpu/drm/gma500/oaktrail_crtc.c:208: warning: 'clock.n' may be used uninitialized in this function

This adds an initialization at declaration time to avoid the warning
and make it well-defined on all compiler versions.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/gpu/drm/gma500/oaktrail_crtc.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/gma500/oaktrail_crtc.c b/drivers/gpu/drm/gma500/oaktrail_crtc.c
index 0fff269d3fe6..b49fe79c3f44 100644
--- a/drivers/gpu/drm/gma500/oaktrail_crtc.c
+++ b/drivers/gpu/drm/gma500/oaktrail_crtc.c
@@ -134,7 +134,7 @@ static bool mrst_sdvo_find_best_pll(const struct gma_limit_t *limit,
struct drm_crtc *crtc, int target,
int refclk, struct gma_clock_t *best_clock)
{
- struct gma_clock_t clock;
+ struct gma_clock_t clock = {};
u32 target_vco, actual_freq;
s32 freq_error, min_error = 100000;

@@ -191,7 +191,7 @@ static bool mrst_lvds_find_best_pll(const struct gma_limit_t *limit,
struct drm_crtc *crtc, int target,
int refclk, struct gma_clock_t *best_clock)
{
- struct gma_clock_t clock;
+ struct gma_clock_t clock = {};
int err = target;

memset(best_clock, 0, sizeof(*best_clock));
--
2.9.0
\
 
 \ /
  Last update: 2017-09-15 22:16    [W:3.874 / U:0.008 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site