diff --git a/boehm-gc/ChangeLog b/boehm-gc/ChangeLog
index fcefa849157d..0d8308365830 100644
--- a/boehm-gc/ChangeLog
+++ b/boehm-gc/ChangeLog
@@ -1,3 +1,9 @@
+2012-05-11  H.J. Lu  <hongjiu.lu@intel.com>
+
+	Merge upstream changes
+	* include/private/gcconfig.h: (ALIGNMENT): Set to 4 for x32.
+	(CPP_WORDSZ): Set to 32 for x32.
+
 2012-02-27  Jack Howarth  <howarth@bromo.med.uc.edu>
 	    Patrick Marlier  <patrick.marlier@gmail.com>
 
diff --git a/boehm-gc/include/private/gcconfig.h b/boehm-gc/include/private/gcconfig.h
index fb09cf73cc0d..0263c13fd885 100644
--- a/boehm-gc/include/private/gcconfig.h
+++ b/boehm-gc/include/private/gcconfig.h
@@ -1974,8 +1974,13 @@
 
 # ifdef X86_64
 #   define MACH_TYPE "X86_64"
-#   define ALIGNMENT 8
-#   define CPP_WORDSZ 64
+#   ifdef __ILP32__
+#     define ALIGNMENT 4
+#     define CPP_WORDSZ 32
+#   else
+#     define ALIGNMENT 8
+#     define CPP_WORDSZ 64
+#   endif
 #   ifndef HBLKSIZE
 #     define HBLKSIZE 4096
 #   endif