Rationalise UNUSED macros. This changeset allows libnsfb to berjek/clang-warnings

built warning-free both with Clang 3.3 (from trunk) and GCC 4.7.

Remove the use of GCC-specific __attribute__ ((unused)) as this
only works on declarations, meaning there is no "fallback" to use
on compilers that are not GCC or clang.  The (void)foo; approach
works with both clang and GCC, and hopefully other compilers
people might be using.

The alternative would to have been two UNUSED macros, one for use
in definitions, and one for use in function bodies.

4 files changed, 27 insertions, 25 deletions

diff --git a/src/plot/16bpp.c b/src/plot/16bpp.c
index d629944..9aa7ab1 100644
--- a/src/plot/16bpp.c
+++ b/src/plot/16bpp.c
@@ -18,23 +18,23 @@
 #include "nsfb.h"
 #include "plot.h"
 
-#define UNUSED __attribute__((unused)) 
-
 static inline uint16_t *get_xy_loc(nsfb_t *nsfb, int x, int y)
 {
         return (void *)(nsfb->ptr + (y * nsfb->linelen) + (x << 1));
 }
 
-static inline nsfb_colour_t pixel_to_colour(UNUSED nsfb_t *nsfb, uint16_t pixel)
+static inline nsfb_colour_t pixel_to_colour(nsfb_t *nsfb, uint16_t pixel)
 {
+	UNUSED(nsfb);
         return ((pixel & 0x1F) << 19) |
               ((pixel & 0x7E0) << 5) |
               ((pixel & 0xF800) >> 8);
 }
 
 /* convert a colour value to a 16bpp pixel value ready for screen output */
-static inline uint16_t colour_to_pixel(UNUSED nsfb_t *nsfb, nsfb_colour_t c)
+static inline uint16_t colour_to_pixel(nsfb_t *nsfb, nsfb_colour_t c)
 {
+	UNUSED(nsfb);
         return ((c & 0xF8) << 8) | ((c & 0xFC00 ) >> 5) | ((c & 0xF80000) >> 19);
 }
 
diff --git a/src/plot/32bpp-xbgr8888.c b/src/plot/32bpp-xbgr8888.c
index 9050903..07613ff 100644
--- a/src/plot/32bpp-xbgr8888.c
+++ b/src/plot/32bpp-xbgr8888.c
@@ -18,36 +18,37 @@
 #include "nsfb.h"
 #include "plot.h"
 
-
-#define UNUSED __attribute__((unused)) 
-
 static inline uint32_t *get_xy_loc(nsfb_t *nsfb, int x, int y)
 {
         return (void *)(nsfb->ptr + (y * nsfb->linelen) + (x << 2));
 }
 
 #if __BYTE_ORDER == __BIG_ENDIAN
-static inline nsfb_colour_t pixel_to_colour(UNUSED nsfb_t *nsfb, uint32_t pixel)
+static inline nsfb_colour_t pixel_to_colour(nsfb_t *nsfb, uint32_t pixel)
 {
+	UNUSED(nsfb);
 	/* TODO: FIX */
         return (pixel >> 8) & ~0xFF000000U;
 }
 
 /* convert a colour value to a 32bpp pixel value ready for screen output */
-static inline uint32_t colour_to_pixel(UNUSED nsfb_t *nsfb, nsfb_colour_t c)
+static inline uint32_t colour_to_pixel(nsfb_t *nsfb, nsfb_colour_t c)
 {
+	UNUSED(nsfb);
 	/* TODO: FIX */
         return (c << 8);
 }
 #else /* __BYTE_ORDER == __BIG_ENDIAN */
-static inline nsfb_colour_t pixel_to_colour(UNUSED nsfb_t *nsfb, uint32_t pixel)
+static inline nsfb_colour_t pixel_to_colour(nsfb_t *nsfb, uint32_t pixel)
 {
+	UNUSED(nsfb);
         return pixel | 0xFF000000U;
 }
 
 /* convert a colour value to a 32bpp pixel value ready for screen output */
-static inline uint32_t colour_to_pixel(UNUSED nsfb_t *nsfb, nsfb_colour_t c)
+static inline uint32_t colour_to_pixel(nsfb_t *nsfb, nsfb_colour_t c)
 {
+	UNUSED(nsfb);
         return c;
 }
 #endif
diff --git a/src/plot/32bpp-xrgb8888.c b/src/plot/32bpp-xrgb8888.c
index 548c970..fb69d91 100644
--- a/src/plot/32bpp-xrgb8888.c
+++ b/src/plot/32bpp-xrgb8888.c
@@ -18,36 +18,37 @@
 #include "nsfb.h"
 #include "plot.h"
 
-
-#define UNUSED __attribute__((unused)) 
-
 static inline uint32_t *get_xy_loc(nsfb_t *nsfb, int x, int y)
 {
         return (void *)(nsfb->ptr + (y * nsfb->linelen) + (x << 2));
 }
 
 #if __BYTE_ORDER == __BIG_ENDIAN
-static inline nsfb_colour_t pixel_to_colour(UNUSED nsfb_t *nsfb, uint32_t pixel)
+static inline nsfb_colour_t pixel_to_colour(nsfb_t *nsfb, uint32_t pixel)
 {
+	UNUSED(nsfb);
         return (pixel >> 8) & ~0xFF000000U;
 }
 
 /* convert a colour value to a 32bpp pixel value ready for screen output */
-static inline uint32_t colour_to_pixel(UNUSED nsfb_t *nsfb, nsfb_colour_t c)
+static inline uint32_t colour_to_pixel(nsfb_t *nsfb, nsfb_colour_t c)
 {
+	UNUSED(nsfb);
         return (c << 8);
 }
 #else /* __BYTE_ORDER == __BIG_ENDIAN */
-static inline nsfb_colour_t pixel_to_colour(UNUSED nsfb_t *nsfb, uint32_t pixel)
+static inline nsfb_colour_t pixel_to_colour(nsfb_t *nsfb, uint32_t pixel)
 {
+	UNUSED(nsfb);
         return ((pixel & 0xFF) << 16) |
                 ((pixel & 0xFF00)) |
                 ((pixel & 0xFF0000) >> 16);
 }
 
 /* convert a colour value to a 32bpp pixel value ready for screen output */
-static inline uint32_t colour_to_pixel(UNUSED nsfb_t *nsfb, nsfb_colour_t c)
+static inline uint32_t colour_to_pixel(nsfb_t *nsfb, nsfb_colour_t c)
 {
+	UNUSED(nsfb);
         return ((c & 0xff0000) >> 16) | (c & 0xff00) | ((c & 0xff) << 16);
 }
 #endif
diff --git a/src/plot/generic.c b/src/plot/generic.c
index 0c3d9e8..87c55c5 100644
--- a/src/plot/generic.c
+++ b/src/plot/generic.c
@@ -605,13 +605,13 @@ copy(nsfb_t *nsfb, nsfb_bbox_t *srcbox, nsfb_bbox_t *dstbox)
 
 static bool arc(nsfb_t *nsfb, int x, int y, int radius, int angle1, int angle2, nsfb_colour_t c)
 {
-    nsfb=nsfb;
-    x = x;
-    y = y;
-    radius = radius;
-    c = c;
-    angle1=angle1;
-    angle2=angle2;
+    UNUSED(nsfb);
+    UNUSED(x);
+    UNUSED(y);
+    UNUSED(radius);
+    UNUSED(c);
+    UNUSED(angle1);
+    UNUSED(angle2);
     return true;
 }