diff -r src/pngread.c src/pngread.c
--- src/pngread.c
+++ src/pngread.c
@@ -132,11 +132,7 @@ int read_png(FILE *fp, unsigned int sig_read, png_bytep **row_pointers,
    /* Expand grayscale images to the full 8 bits from 1, 2, or 4 bits/pixel */
    if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
    {
-#if defined(__APPLE__) || defined(__WIN32) || defined(__WIN64)
 	   png_set_expand_gray_1_2_4_to_8(png_ptr);
-#else
-      png_set_gray_1_2_4_to_8(png_ptr);
-#endif
 	}
 	
    /* Expand paletted or RGB images with transparency to full alpha for RGBA */