prevents loss of key object if the format object (where key stored) becomes changed (loses its internal representation during evals);

should avoid possible theoretical segfault there.

1 files changed, 14 insertions, 12 deletions

diff --git a/generic/tclClockFmt.c b/generic/tclClockFmt.c
index d875bd4..18b82fa 100644
--- a/generic/tclClockFmt.c
+++ b/generic/tclClockFmt.c
@@ -634,7 +634,7 @@ ClockFmtObj_UpdateString(objPtr)
  *
  *	This is normally stored in second pointer of internal representation.
  *	If format object is not localizable, it is equal the given format 
- *	pointer and the first pointer of internal representation may be NULL.
+ *	pointer (special case to fast fallback by not-localizable formats).
  *
  * Results:
  *	Returns tcl object with key or format object if not localizable.
@@ -825,16 +825,20 @@ ClockLocalizeFormat(
 	return opts->formatObj;
     }
 
+    /* prevents loss of key object if the format object (where key stored) 
+     * becomes changed (loses its internal representation during evals) */
+    Tcl_IncrRefCount(keyObj);
+
     if (opts->mcDictObj == NULL) {
 	ClockMCDict(opts);
 	if (opts->mcDictObj == NULL)
-	    return NULL;
+	    goto done;
     }
 
     /* try to find in cache within locale mc-catalog */
     if (Tcl_DictObjGet(NULL, opts->mcDictObj, 
 	    keyObj, &valObj) != TCL_OK) {
-	return NULL;
+	goto done;
     }
 
     /* call LocalizeFormat locale format fmtkey */
@@ -844,10 +848,9 @@ ClockLocalizeFormat(
 	callargs[1] = opts->localeObj;
 	callargs[2] = opts->formatObj;
 	callargs[3] = keyObj;
-	Tcl_IncrRefCount(keyObj);
 	if (Tcl_EvalObjv(opts->interp, 4, callargs, 0) != TCL_OK
 	) {
-	    goto clean;
+	    goto done;
 	}
 
 	valObj = Tcl_GetObjResult(opts->interp);
@@ -857,9 +860,11 @@ ClockLocalizeFormat(
 		keyObj, valObj) != TCL_OK
 	) {
 	    valObj = NULL;
-	    goto clean;
+	    goto done;
 	}
 
+	Tcl_ResetResult(opts->interp);
+
 	/* check special case - format object is not localizable */
 	if (valObj == opts->formatObj) {
 	    /* mark it as unlocalizable, by setting self as key (without refcount incr) */
@@ -868,14 +873,11 @@ ClockLocalizeFormat(
 		ObjLocFmtKey(opts->formatObj) = opts->formatObj;
 	    }
 	}
-clean:
-
-	Tcl_UnsetObjRef(keyObj);
-	if (valObj) {
-	    Tcl_ResetResult(opts->interp);
-	}
     }
 
+done:
+
+    Tcl_UnsetObjRef(keyObj);
     return (opts->formatObj = valObj);
 }