Bug 93 - Build fails on ARM with static assert 8u == 4u

libphobos/libdruntime/gcc/deh.d

@@ -58,26 +58,14 @@ else
 
 struct d_exception_header
 {
-  version (GNU_ARM_EABI_Unwinder)
-  {
-    // Nothing here yet.
-  }
-  else
-  {
-    // Cache handler details between Phase 1 and Phase 2.
-    int handlerSwitchValue;
-    ubyte *actionRecord;
-    ubyte *languageSpecificData;
-    _Unwind_Ptr catchTemp;
-  }
-
   // The object being thrown.  Like GCJ, the compiled code expects this to 
   // be immediately before the generic exception header.
   // (See build_exception_object)
   enum UNWIND_PAD = (Object.alignof < _Unwind_Exception.alignof)
     ? _Unwind_Exception.alignof - Object.alignof : 0;
 
-  // FIXME: padding should be aligned max for target.
+  // Because of a lack of __aligned__ style attribute, our object
+  // and the unwind object are the first two fields.
   ubyte[UNWIND_PAD] pad;
 
   Object object;
@@ -86,12 +74,26 @@ struct d_exception_header
   _Unwind_Exception unwindHeader;
 
   static assert(unwindHeader.offsetof - object.offsetof == object.sizeof);
+
+  version (GNU_ARM_EABI_Unwinder)
+  {
+    // Nothing here yet.
+  }
+  else
+  {
+    // Cache handler details between Phase 1 and Phase 2.
+    int handlerSwitchValue;
+    ubyte *actionRecord;
+    ubyte *languageSpecificData;
+    _Unwind_Ptr catchTemp;
+  }
 }
 
 private d_exception_header *
 get_exception_header_from_ue(_Unwind_Exception *exc)
 {
-  return cast(d_exception_header *)(exc + 1) - 1;
+  return cast(d_exception_header *)
+    (cast(void *) exc - d_exception_header.unwindHeader.offsetof);
 }
 
 // D doesn't define these, so they are private for now.