diff --git a/common/rfb/CMsgReader.cxx b/common/rfb/CMsgReader.cxx
index 1d359d2..e42546d 100644
--- a/common/rfb/CMsgReader.cxx
+++ b/common/rfb/CMsgReader.cxx
@@ -210,7 +210,7 @@
   if (width > maxCursorSize || height > maxCursorSize)
     throw Exception("Too big cursor");
 
-  rdr::U8 buf[width*height*4];
+  rdr::U8Array rgba(width*height*4);
 
   if (width * height > 0) {
     rdr::U8 pr, pg, pb;
@@ -235,7 +235,7 @@
     is->readBytes(mask.buf, mask_len);
 
     int maskBytesPerRow = (width+7)/8;
-    out = buf;
+    out = rgba.buf;
     for (y = 0;y < height;y++) {
       for (x = 0;x < width;x++) {
         int byte = y * maskBytesPerRow + x / 8;
@@ -261,7 +261,7 @@
     }
   }
 
-  handler->setCursor(width, height, hotspot, buf);
+  handler->setCursor(width, height, hotspot, rgba.buf);
 }
 
 void CMsgReader::readSetCursor(int width, int height, const Point& hotspot)
@@ -275,7 +275,7 @@
   rdr::U8Array mask(mask_len);
 
   int x, y;
-  rdr::U8 buf[width*height*4];
+  rdr::U8Array rgba(width*height*4);
   rdr::U8* in;
   rdr::U8* out;
 
@@ -284,7 +284,7 @@
 
   int maskBytesPerRow = (width+7)/8;
   in = data.buf;
-  out = buf;
+  out = rgba.buf;
   for (y = 0;y < height;y++) {
     for (x = 0;x < width;x++) {
       int byte = y * maskBytesPerRow + x / 8;
@@ -302,7 +302,7 @@
     }
   }
 
-  handler->setCursor(width, height, hotspot, buf);
+  handler->setCursor(width, height, hotspot, rgba.buf);
 }
 
 void CMsgReader::readSetCursorWithAlpha(int width, int height, const Point& hotspot)
diff --git a/common/rfb/Cursor.cxx b/common/rfb/Cursor.cxx
index 99df82d..d0feaa5 100644
--- a/common/rfb/Cursor.cxx
+++ b/common/rfb/Cursor.cxx
@@ -76,7 +76,7 @@
 }
 
 // Floyd-Steinberg dithering
-static void dither(int width, int height, int* data)
+static void dither(int width, int height, rdr::U16* data)
 {
   for (int y = 0; y < height; y++) {
     for (int x_ = 0; x_ < width; x_++) {
@@ -122,31 +122,33 @@
 rdr::U8* Cursor::getBitmap() const
 {
   // First step is converting to luminance
-  int luminance[width()*height()];
-  int *lum_ptr = luminance;
+  rdr::U16Array luminance(width()*height());
+  rdr::U16 *lum_ptr = luminance.buf;
   const rdr::U8 *data_ptr = data;
   for (int y = 0; y < height(); y++) {
     for (int x = 0; x < width(); x++) {
-      // Use BT.709 coefficients for grayscale
-      *lum_ptr = 0;
-      *lum_ptr += (int)srgb_to_lin(data_ptr[0]) * 6947;  // 0.2126
-      *lum_ptr += (int)srgb_to_lin(data_ptr[1]) * 23436; // 0.7152
-      *lum_ptr += (int)srgb_to_lin(data_ptr[2]) * 2366;  // 0.0722
-      *lum_ptr /= 32768;
+      rdr::U32 lum;
 
-      lum_ptr++;
+      // Use BT.709 coefficients for grayscale
+      lum = 0;
+      lum += (rdr::U32)srgb_to_lin(data_ptr[0]) * 6947;  // 0.2126
+      lum += (rdr::U32)srgb_to_lin(data_ptr[1]) * 23436; // 0.7152
+      lum += (rdr::U32)srgb_to_lin(data_ptr[2]) * 2366;  // 0.0722
+      lum /= 32768;
+
+      *lum_ptr++ = lum;
       data_ptr += 4;
     }
   }
 
   // Then diterhing
-  dither(width(), height(), luminance);
+  dither(width(), height(), luminance.buf);
 
   // Then conversion to a bit mask
   rdr::U8Array source((width()+7)/8*height());
   memset(source.buf, 0, (width()+7)/8*height());
   int maskBytesPerRow = (width() + 7) / 8;
-  lum_ptr = luminance;
+  lum_ptr = luminance.buf;
   data_ptr = data;
   for (int y = 0; y < height(); y++) {
     for (int x = 0; x < width(); x++) {
@@ -165,25 +167,24 @@
 rdr::U8* Cursor::getMask() const
 {
   // First step is converting to integer array
-  int alpha[width()*height()];
-  int *alpha_ptr = alpha;
+  rdr::U16Array alpha(width()*height());
+  rdr::U16 *alpha_ptr = alpha.buf;
   const rdr::U8 *data_ptr = data;
   for (int y = 0; y < height(); y++) {
     for (int x = 0; x < width(); x++) {
-      *alpha_ptr = (int)data_ptr[3] * 65535 / 255;
-      alpha_ptr++;
+      *alpha_ptr++ = (rdr::U32)data_ptr[3] * 65535 / 255;
       data_ptr += 4;
     }
   }
 
   // Then diterhing
-  dither(width(), height(), alpha);
+  dither(width(), height(), alpha.buf);
 
   // Then conversion to a bit mask
   rdr::U8Array mask((width()+7)/8*height());
   memset(mask.buf, 0, (width()+7)/8*height());
   int maskBytesPerRow = (width() + 7) / 8;
-  alpha_ptr = alpha;
+  alpha_ptr = alpha.buf;
   data_ptr = data;
   for (int y = 0; y < height(); y++) {
     for (int x = 0; x < width(); x++) {
diff --git a/common/rfb/TightDecoder.cxx b/common/rfb/TightDecoder.cxx
index cc786f5..c547053 100644
--- a/common/rfb/TightDecoder.cxx
+++ b/common/rfb/TightDecoder.cxx
@@ -266,15 +266,16 @@
       buflen -= 1;
 
       if (pf.is888()) {
-        rdr::U8 tightPalette[palSize * 3];
+        size_t len = palSize * 3;
+        rdr::U8Array tightPalette(len);
 
-        assert(buflen >= sizeof(tightPalette));
+        assert(buflen >= sizeof(len));
 
-        memcpy(tightPalette, bufptr, sizeof(tightPalette));
-        bufptr += sizeof(tightPalette);
-        buflen -= sizeof(tightPalette);
+        memcpy(tightPalette.buf, bufptr, len);
+        bufptr += len;
+        buflen -= len;
 
-        pf.bufferFromRGB(palette, tightPalette, palSize);
+        pf.bufferFromRGB(palette, tightPalette.buf, palSize);
       } else {
         size_t len;