diff --git a/reactos/subsys/win32k/dib/dib16bpp.c b/reactos/subsys/win32k/dib/dib16bpp.c
index 906308ecb56..b4e4acb08ad 100644
--- a/reactos/subsys/win32k/dib/dib16bpp.c
+++ b/reactos/subsys/win32k/dib/dib16bpp.c
@@ -53,7 +53,7 @@ DIB_16BPP_HLine(SURFOBJ *SurfObj, LONG x1, LONG x2, LONG y, ULONG c)
 "  shl  $16, %%eax\n"
 "  andl $0xffff, %0\n"  /* If the pixel value is "abcd", put "abcdabcd" in %eax */
 "  or   %0, %%eax\n"
-"  test $0x01, %%edi\n" /* Align to fullword boundary */
+"  test $0x03, %%edi\n" /* Align to fullword boundary */
 "  jz   .L1\n"
 "  stosw\n"
 "  dec  %1\n"
diff --git a/reactos/subsys/win32k/eng/lineto.c b/reactos/subsys/win32k/eng/lineto.c
index 27785358a2d..b162a053a11 100644
--- a/reactos/subsys/win32k/eng/lineto.c
+++ b/reactos/subsys/win32k/eng/lineto.c
@@ -381,6 +381,11 @@ EngLineTo(SURFOBJ *DestObj,
   deltax = x2 - x1;
   deltay = y2 - y1;
 
+  if (0 == deltax && 0 == deltay)
+    {
+      return TRUE;
+    }
+
   if (deltax < 0)
     {
       xchange = -1;