diff -r a3f734a23566 -r 1e749c7b70f8 lib/iec_types.h
--- a/lib/iec_types.h	Sun Jun 01 08:59:57 2014 +0100
+++ b/lib/iec_types.h	Sat Jul 05 13:39:30 2014 +0100
@@ -29,6 +29,11 @@
 typedef float    IEC_REAL;
 typedef double   IEC_LREAL;
 
+/* WARNING: When editing the definition of IEC_TIMESPEC, take note that 
+ *          if the order of the two elements 'tv_sec' and 'tv_nsec' is changed, then the macros 
+ *          __time_to_timespec() and __tod_to_timespec() will need to be changed accordingly.
+ *          (these macros may be found in iec_std_lib.h)
+ */
 typedef struct {
     long int tv_sec;            /* Seconds.  */
     long int tv_nsec;           /* Nanoseconds.  */