-void GL_Upload32 (void *data, int width, int height, qboolean mipmap, qboolean alpha);
-void GL_Upload8 (byte *data, int width, int height, qboolean mipmap, qboolean alpha);
-int GL_LoadTexture (char *identifier, int width, int height, byte *data, qboolean mipmap, qboolean alpha, int bytesperpixel);
-int GL_FindTexture (char *identifier);
+extern void GL_Upload32 (void *data, int width, int height, qboolean mipmap, qboolean alpha);
+extern void GL_Upload8 (byte *data, int width, int height, qboolean mipmap, qboolean alpha);
+extern int GL_LoadTexture (char *identifier, int width, int height, byte *data, qboolean mipmap, qboolean alpha, int bytesperpixel);
+extern int GL_FindTexture (char *identifier);