diff --git macosx/tclMacOSXFCmd.c macosx/tclMacOSXFCmd.c
index 6275aac40..66582efe0 100644
--- macosx/tclMacOSXFCmd.c
+++ macosx/tclMacOSXFCmd.c
@@ -142,7 +142,7 @@ TclMacOSXGetFileAttribute(
     struct attrlist alist;
     fileinfobuf finfo;
     finderinfo *finder = (finderinfo *) &finfo.data;
-    off_t *rsrcForkSize = (off_t *) &finfo.data;
+    off_t rsrcForkSize;
     const char *native;
 
     result = TclpObjStat(fileName, &statBuf);
@@ -196,7 +196,9 @@ TclMacOSXGetFileAttribute(
 		(finder->fdFlags & kFinfoIsInvisible) != 0);
 	break;
     case MACOSX_RSRCLENGTH_ATTRIBUTE:
+	/* finfo.data is not necessarily 8-byte aligned */
+	memcpy(&rsrcForkSize, &finfo.data, sizeof(rsrcForkSize));
-	*attributePtrPtr = Tcl_NewWideIntObj(*rsrcForkSize);
+	*attributePtrPtr = Tcl_NewWideIntObj(rsrcForkSize);
 	break;
     }
     return TCL_OK;
@@ -238,7 +240,7 @@ TclMacOSXSetFileAttribute(
     struct attrlist alist;
     fileinfobuf finfo;
     finderinfo *finder = (finderinfo *) &finfo.data;
-    off_t *rsrcForkSize = (off_t *) &finfo.data;
+    off_t rsrcForkSize;
     const char *native;
 
     result = TclpObjStat(fileName, &statBuf);
@@ -324,7 +326,9 @@ TclMacOSXSetFileAttribute(
 	    return TCL_ERROR;
 	}
 
+	/* finfo.data is not necessarily 8-byte aligned */
+	memcpy(&rsrcForkSize, &finfo.data, sizeof(rsrcForkSize));
-	if (newRsrcForkSize != *rsrcForkSize) {
+	if (newRsrcForkSize != rsrcForkSize) {
 	    Tcl_DString ds;
 
 	    /*
