Index: cfe/trunk/include/clang/Basic/TargetInfo.h
===================================================================
--- cfe/trunk/include/clang/Basic/TargetInfo.h
+++ cfe/trunk/include/clang/Basic/TargetInfo.h
@@ -413,10 +413,10 @@
   }
 
   // Return the size of unwind_word for this target.
-  unsigned getUnwindWordWidth() const { return getPointerWidth(0); }
+  virtual unsigned getUnwindWordWidth() const { return getPointerWidth(0); }
 
   /// \brief Return the "preferred" register width on this target.
-  unsigned getRegisterWidth() const {
+  virtual unsigned getRegisterWidth() const {
     // Currently we assume the register width on the target matches the pointer
     // width, we can introduce a new variable for this if/when some target wants
     // it.
Index: cfe/trunk/lib/Basic/Targets.cpp
===================================================================
--- cfe/trunk/lib/Basic/Targets.cpp
+++ cfe/trunk/lib/Basic/Targets.cpp
@@ -4029,6 +4029,8 @@
 
   // for x32 we need it here explicitly
   bool hasInt128Type() const override { return true; }
+  unsigned getUnwindWordWidth() const override { return 64; }
+  unsigned getRegisterWidth() const override { return 64; }
 
   bool validateGlobalRegisterVariable(StringRef RegName,
                                       unsigned RegSize,
Index: cfe/trunk/lib/Sema/SemaDeclAttr.cpp
===================================================================
--- cfe/trunk/lib/Sema/SemaDeclAttr.cpp
+++ cfe/trunk/lib/Sema/SemaDeclAttr.cpp
@@ -3332,7 +3332,7 @@
     // FIXME: glibc uses 'word' to define register_t; this is narrower than a
     // pointer on PIC16 and other embedded platforms.
     if (Str == "word")
-      DestWidth = S.Context.getTargetInfo().getPointerWidth(0);
+      DestWidth = S.Context.getTargetInfo().getRegisterWidth();
     else if (Str == "byte")
       DestWidth = S.Context.getTargetInfo().getCharWidth();
     break;
Index: cfe/trunk/test/Sema/attr-mode.c
===================================================================
--- cfe/trunk/test/Sema/attr-mode.c
+++ cfe/trunk/test/Sema/attr-mode.c
@@ -4,6 +4,8 @@
 // RUN:   -verify %s
 // RUN: %clang_cc1 -triple powerpc64-pc-linux-gnu -DTEST_64BIT_PPC64 -fsyntax-only \
 // RUN:   -verify %s
+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnux32 -DTEST_64BIT_X86 -fsyntax-only \
+// RUN:   -verify %s
 
 typedef int i16_1 __attribute((mode(HI)));
 int i16_1_test[sizeof(i16_1) == 2 ? 1 : -1];
@@ -63,8 +65,17 @@
 void test_long_to_i64(long long* y) { f_i64_arg(y); }
 void test_long_to_ui64(unsigned long long* y) { f_ui64_arg(y); }
 #elif TEST_64BIT_X86
+#ifdef __ILP32__
+typedef unsigned int gcc_word __attribute__((mode(word)));
+int foo[sizeof(gcc_word) == 8 ? 1 : -1];
+typedef unsigned int gcc_unwind_word __attribute__((mode(unwind_word)));
+int foo[sizeof(gcc_unwind_word) == 8 ? 1 : -1];
+void test_long_to_i64(long long* y) { f_i64_arg(y); }
+void test_long_to_ui64(unsigned long long* y) { f_ui64_arg(y); }
+#else
 void test_long_to_i64(long* y) { f_i64_arg(y); }
 void test_long_to_ui64(unsigned long* y) { f_ui64_arg(y); }
+#endif
 typedef          float f128ibm __attribute__ ((mode (TF)));     // expected-error{{unsupported machine mode 'TF'}}
 #elif TEST_64BIT_PPC64
 typedef          float f128ibm __attribute__ ((mode (TF)));