dos: make sure we don't look like a Windows image

Some tools might assume that the reloc offset being 64 automatically
means it's really a Windows file.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>

diff --git a/dos/header.S b/dos/header.S
index e750447..8367078 100644 (file)
--- a/dos/header.S
+++ b/dos/header.S
@@ -18,6 +18,12 @@ __header_start:
                .short  _exe_text_seg   /* CS */
                .short  __reloc
                .short  0               /* Overlay number */
+/*
+ * Don't put these fields in unless we actually have an NE or PE image;
+ * some tools might get confused and assume __reloc = 64 automatically
+ * means an NE/PE image or a Windows image of some sort.
+ */
+#if 0
                .short  0               /* Unknown/pad? */
                .short  0               /* Unknown/pad? */
                .short  0               /* Unknown/pad? */
@@ -35,6 +41,8 @@ __header_start:
                .short  0               /* Unknown/pad? */
                .short  0               /* Unknown/pad? */
                .long   0               /* Pointer to Windows PE header */
+#endif
+               .balign 4
 __reloc:
                .balign 512
 __header_end: