diff --git a/src/external/win32_clipboard.h b/src/external/win32_clipboard.h
index 1cb05457d..c85b3882a 100644
--- a/src/external/win32_clipboard.h
+++ b/src/external/win32_clipboard.h
@@ -178,7 +178,9 @@ typedef struct tagRGBQUAD {
 #define BI_CMYK      0x000B
 #define BI_CMYKRLE8  0x000C
 #define BI_CMYKRLE4  0x000D
+#endif
 
+#ifndef BI_ALPHABITFIELDS
 // Bitmap not compressed and that the color table consists of four DWORD color masks, 
 // that specify the red, green, blue, and alpha components of each pixel
 #define BI_ALPHABITFIELDS 0x0006
@@ -317,7 +319,7 @@ static int GetPixelDataOffset(BITMAPINFOHEADER bih)
             // If (bih.biCompression == BI_RGB) no need to be offset more
 
             if (bih.biCompression == BI_BITFIELDS) offset += 3*rgbaSize;
-            else if (bih.biCompression == BI_ALPHABITFIELDS) offset += 4*rgbaSize; // Not widely supported, but valid
+            else if (bih.biCompression == BI_ALPHABITFIELDS) offset += 4 * rgbaSize; // Not widely supported, but valid
         }
     }