diff --git a/winsup/mingw/ChangeLog b/winsup/mingw/ChangeLog
index edf023911..b0f749390 100644
--- a/winsup/mingw/ChangeLog
+++ b/winsup/mingw/ChangeLog
@@ -1,3 +1,8 @@
+2012-08-01  Earnie Boyd  <earnie@users.sourceforge.net>
+
+	* include/excpt.h (__try1): Define based on _WIN64 definition.
+	(__except1): Ditto.
+
 2012-07-30  Earnie Boyd  <earnie@users.sourceforge.net>
 
 	* include/stdint.h: Include _mingw.h for the definition of __int64 when
diff --git a/winsup/mingw/include/excpt.h b/winsup/mingw/include/excpt.h
index e75ceb78f..3919cb791 100644
--- a/winsup/mingw/include/excpt.h
+++ b/winsup/mingw/include/excpt.h
@@ -75,8 +75,15 @@ typedef PEXCEPTION_REGISTRATION PEXCEPTION_REGISTRATION_RECORD;
  * onto the stack, then put a pointer to the new registration
  * structure (i.e. the current stack pointer) at fs:0.
  */
-#define __try1(pHandler) \
-	__asm__ ("pushl %0;pushl %%fs:0;movl %%esp,%%fs:0;" : : "g" (pHandler));
+#ifdef _WIN64
+# define __try1(pHandler) \
+	__asm__ __volatile__ ("pushq %0;pushq %%gs:0;movq %%rsp,%%gs:0;" : : \
+	"g" (pHandler));
+#else
+# define __try1(pHandler) \
+	__asm__ __volatile__ ("pushl %0;pushl %%fs:0;movl %%esp,%%fs:0;" : : \
+	"g" (pHandler));
+#endif
 
 /*
  * A macro which (despite its name) *removes* an installed
@@ -89,9 +96,15 @@ typedef PEXCEPTION_REGISTRATION PEXCEPTION_REGISTRATION_RECORD;
  * the stack must be in the exact state at this point that it was
  * after we did __try1 or this will smash things.
  */
-#define	__except1	\
-	__asm__ ("movl (%%esp),%%eax;movl %%eax,%%fs:0;addl $8,%%esp;" \
-	 : : : "%eax");
+#ifdef _WIN64
+# define	__except1	\
+	__asm__ __volatile__ ("movq (%%rsp),%%rax;movq %%rax,%%gs:0;addq \
+	$16,%%rsp;" : : : "%rax");
+#else
+# define __except1	\
+	__asm__ __volatile__ ("movl (%%esp),%%eax;movl %%eax,%%fs:0;addl \
+	$8,%%esp;" : : : "%eax");
+#endif
 
 #ifdef	__cplusplus
 }