diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 9fba87f5cb6..5aeb1303634 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2005-06-13  Mark Mitchell  <mark@codesourcery.com>
+
+	* config/i386/x86-64.h (ASM_SPEC): Explicitly pass --64 to the
+	assembler in 64-bit mode.
+
 2005-06-13  David Edelsohn  <edelsohn@gnu.org>
 
 	Revert scc_operand patch.
diff --git a/gcc/config/i386/x86-64.h b/gcc/config/i386/x86-64.h
index e6aa6204bef..e900e436b68 100644
--- a/gcc/config/i386/x86-64.h
+++ b/gcc/config/i386/x86-64.h
@@ -49,7 +49,7 @@ Boston, MA 02111-1307, USA.  */
 
 #undef ASM_SPEC
 #define ASM_SPEC "%{v:-V} %{Qy:} %{!Qn:-Qy} %{n} %{T} %{Ym,*} %{Yd,*} \
- %{Wa,*:%*} %{m32:--32}"
+ %{Wa,*:%*} %{m32:--32} %{m64:--64}"
 
 #define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN) \
   asm_output_aligned_bss (FILE, DECL, NAME, SIZE, ALIGN)