diff --git a/drivers/bios_emulator/atibios.c b/drivers/bios_emulator/atibios.c
index 77172467b2e18141c7f88b786f026ec6a084d7cf..2d5b5dc562e06473ce6d19baeba44c90698b98d1 100644
--- a/drivers/bios_emulator/atibios.c
+++ b/drivers/bios_emulator/atibios.c
@@ -599,7 +599,7 @@ int biosemu_run(pci_dev_t pcidev, uchar *bios_rom, int bios_len,
 	if (clean_up) {
 		BE_exit();
 		if (vga_info->BIOSImage &&
-		    (u32)(vga_info->BIOSImage) != 0xc0000)
+		    (ulong)(vga_info->BIOSImage) != 0xc0000)
 			free(vga_info->BIOSImage);
 		free(vga_info);
 		vga_info = NULL;