Marshal now works with nil strings. Timezone and tzname vars are not public any more in the times module.

lib/core/typeinfo.nim

@@ -479,7 +479,8 @@ proc setBiggestFloat*(x: TAny, y: biggestFloat) =
 proc getString*(x: TAny): string = 
   ## retrieve the string value out of `x`. `x` needs to represent a string.
   assert x.rawtype.kind == tyString
-  result = cast[ptr string](x.value)[]
+  if not isNil(cast[ptr pointer](x.value)[]):
+    result = cast[ptr string](x.value)[]
 
 proc setString*(x: TAny, y: string) = 
   ## sets the string value of `x`. `x` needs to represent a string.

lib/pure/times.nim

@@ -26,8 +26,8 @@ type
     dMon, dTue, dWed, dThu, dFri, dSat, dSun
 
 var
-  timezone* {.importc, header: "<time.h>".}: int
-  tzname* {.importc, header: "<time.h>" .}: array[0..1, cstring]
+  timezone {.importc, header: "<time.h>".}: int
+  tzname {.importc, header: "<time.h>" .}: array[0..1, cstring]
 
 when defined(posix): 
   type