diff --git a/contrib/arm-neon/linux-auxv.c b/contrib/arm-neon/linux-auxv.c
index 696e297ef..4d26bd3b3 100644
--- a/contrib/arm-neon/linux-auxv.c
+++ b/contrib/arm-neon/linux-auxv.c
@@ -7,7 +7,7 @@
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
- * 
+ *
  * SEE contrib/arm-neon/README before reporting bugs
  *
  * STATUS: COMPILED, TESTED
diff --git a/contrib/arm-neon/linux.c b/contrib/arm-neon/linux.c
index abae9e33b..94f9bb1e0 100644
--- a/contrib/arm-neon/linux.c
+++ b/contrib/arm-neon/linux.c
@@ -72,7 +72,7 @@ png_have_neon(png_structp png_ptr)
                      state = Colon;
                   break;
                }
-               
+
                /* did not match 'feature' */
                state = SkipLine;
                /* FALL THROUGH */
diff --git a/contrib/examples/simpleover.c b/contrib/examples/simpleover.c
index 6852a9574..59dd31368 100644
--- a/contrib/examples/simpleover.c
+++ b/contrib/examples/simpleover.c
@@ -136,7 +136,7 @@ sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
             /* This is the optimized Porter-Duff 'Over' operation, when the
              * input alpha is 0 the output is not changed.
              */
-            if (in_alpha > 0) 
+            if (in_alpha > 0)
             {
                png_uint_16 *out_pixel = sprite->buffer +
                   ((y+y_offset) * sprite->width + (x+x_offset))*4;
@@ -184,7 +184,7 @@ sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
    }
 }
 
-static int 
+static int
 create_sprite(struct sprite *sprite, int *argc, const char ***argv)
 {
    /* Read the arguments and create this sprite. The sprite buffer has already
@@ -415,7 +415,7 @@ simpleover_process(png_imagep output, png_bytep out_buf, int argc,
             n = sscanf(argv[0], "--sprite=%u,%u,%" str(sprite_name_chars) "s%c",
                 &sprites[nsprites].width, &sprites[nsprites].height,
                 sprites[nsprites].name, &tombstone);
-            
+
             if ((n == 2 || n == 3) &&
                 sprites[nsprites].width > 0 && sprites[nsprites].height > 0)
             {
@@ -492,7 +492,7 @@ simpleover_process(png_imagep output, png_bytep out_buf, int argc,
                if (!add_sprite(output, out_buf, sprites+isprite, &argc, &argv))
                   goto out; /* error in add_sprite */
 
-               break; 
+               break;
             }
          }
 
diff --git a/contrib/gregbook/rpng2-x.c b/contrib/gregbook/rpng2-x.c
index eea95fbd4..0c8ddeba2 100644
--- a/contrib/gregbook/rpng2-x.c
+++ b/contrib/gregbook/rpng2-x.c
@@ -496,12 +496,12 @@ int main(int argc, char **argv)
           "\t\t  transparent images; overrides -bgcolor\n",
           num_bgpat-1);
 #ifdef FEATURE_LOOP
-        fprintf(stderr, 
+        fprintf(stderr,
           "    -loop\tloops through background images after initial display\n"
           "\t\t  is complete (depends on -bgpat)\n"
           "    sec \tseconds to display each background image (default = 2)\n");
 #endif
-        fprintf(stderr, 
+        fprintf(stderr,
           "    dur \tduration in microseconds to wait after displaying each\n"
           "\t\t  row (for demo purposes)\n"
           "    -timing\tenables delay for every block read, to simulate modem\n"
diff --git a/contrib/libtests/makepng.c b/contrib/libtests/makepng.c
index 1d3a0addd..60d96d198 100644
--- a/contrib/libtests/makepng.c
+++ b/contrib/libtests/makepng.c
@@ -392,7 +392,7 @@ generate_row(png_bytep row, size_t rowbytes, unsigned int y, int color_type,
    unsigned int *colors, int small)
 {
    int filters = 0; /* file *MASK*, 0 means the default, not NONE */
-   png_uint_32 size_max = 
+   png_uint_32 size_max =
       image_size_of_type(color_type, bit_depth, colors, small)-1;
    png_uint_32 depth_max = (1U << bit_depth)-1; /* up to 65536 */
 
@@ -526,7 +526,7 @@ generate_row(png_bytep row, size_t rowbytes, unsigned int y, int color_type,
             assert(0/*NOT REACHED*/);
       }
    }
-      
+
    else switch (channels_of_type(color_type))
    {
    /* 1 channel: a square image with a diamond, the least luminous colors are on
@@ -1913,7 +1913,7 @@ main(int argc, char **argv)
       };
 
       chunk_insert *new_insert;
-      
+
       new_insert = add_tEXt("Copyright", copyright);
       if (new_insert != NULL)
       {
diff --git a/contrib/libtests/pngstest.c b/contrib/libtests/pngstest.c
index 44267b4fb..3374c7202 100644
--- a/contrib/libtests/pngstest.c
+++ b/contrib/libtests/pngstest.c
@@ -3130,7 +3130,7 @@ write_one_file(Image *output, Image *image, int convert_to_8bit)
         (void) unlink(tmpfile);
       }
 #endif
-      
+
       if (f != NULL)
       {
          if (png_image_write_to_stdio(&image->image, f, convert_to_8bit,
diff --git a/contrib/libtests/pngvalid.c b/contrib/libtests/pngvalid.c
index 94d37a27a..50abd409b 100644
--- a/contrib/libtests/pngvalid.c
+++ b/contrib/libtests/pngvalid.c
@@ -4038,7 +4038,7 @@ make_size_image(png_store* const ps, png_byte const colour_type,
                 */
                {
                   int filters;
-                  
+
                   RANDOMIZE(filters);
                   filters %= PNG_FILTER_VALUE_LAST;
                   if (filters < 0) filters = -filters;
diff --git a/contrib/neon/neon.am b/contrib/neon/neon.am
index f20d59e4a..c45777bed 100644
--- a/contrib/neon/neon.am
+++ b/contrib/neon/neon.am
@@ -1,7 +1,7 @@
 # contrib/neon/neon.am
 #
 # This is an automake fragment included by the top-level Makefile.am if
-# contrib/neon/neon.ac is included in configure 
+# contrib/neon/neon.ac is included in configure
 #
 # It builds the source files in this directory into ARM hardware support for
 # libpng.
diff --git a/contrib/tools/genpng.c b/contrib/tools/genpng.c
index 44102b4d6..ce43260cb 100644
--- a/contrib/tools/genpng.c
+++ b/contrib/tools/genpng.c
@@ -324,7 +324,7 @@ alpha_calc(const struct arg *arg, double x, double y)
                {
                   double wx = bicubic[abs(dx)][0];
 
-                  if (wx != 0 && arg->inside_fn(arg, x+dx/16, y+dy/16)) 
+                  if (wx != 0 && arg->inside_fn(arg, x+dx/16, y+dy/16))
                      alphay += wx;
                }
 
@@ -565,7 +565,7 @@ line_check(double x, double y, double x1, double y1, double x2, double y2,
    /* The dot product is the distance down the line, the cross product is
     * the distance away from the line:
     *
-    *    distance = |cross| / sqrt(len2) 
+    *    distance = |cross| / sqrt(len2)
     */
    cross = x * ly - y * lx;
 
@@ -722,7 +722,7 @@ pixel(png_uint_16p p, struct arg *args, int nargs, double x, double y)
    /* 'a' may be negative or greater than 1; if it is, negative clamp the
     * pixel to 0 if >1 clamp r/g/b:
     */
-   if (a > 0) 
+   if (a > 0)
    {
       if (a > 1)
       {
diff --git a/contrib/tools/png-fix-itxt.c b/contrib/tools/png-fix-itxt.c
index 5730d9f79..c7654c113 100644
--- a/contrib/tools/png-fix-itxt.c
+++ b/contrib/tools/png-fix-itxt.c
@@ -8,7 +8,7 @@
  * For conditions of distribution and use, see the disclaimer
  * and license in png.h
  *
- * Usage:            
+ * Usage:
  *
  *     png-fix-itxt.exe < bad.png > good.png
  *