diff --git a/xpcom/base/nsISupportsObsolete.h b/xpcom/base/nsISupportsObsolete.h
index ff60154e53e..874d859fbfd 100644
--- a/xpcom/base/nsISupportsObsolete.h
+++ b/xpcom/base/nsISupportsObsolete.h
@@ -88,21 +88,24 @@ _method(_type aResult) \
  * special for strings to get/set char* strings
  * using PL_strdup and PR_FREEIF
  */
-#define NS_METHOD_GETTER_STR(_method,_member) \
-_method(char* *aString)\
-{\
+#define NS_METHOD_GETTER_STR(_method,_member)   \
+_method(char* *aString)                         \
+{                                               \
     if (!aString) return NS_ERROR_NULL_POINTER; \
-    *aString = PL_strdup(_member); \
-    return NS_OK; \
+    if (!(*aString = PL_strdup(_member)))       \
+      return NS_ERROR_OUT_OF_MEMORY;            \
+    return NS_OK;                               \
 }
 
 #define NS_METHOD_SETTER_STR(_method, _member) \
-_method(const char *aString)\
-{\
-    PR_FREEIF(_member);\
-    if (aString) _member = PL_strdup(aString); \
-    else _member = nsnull;\
-    return NS_OK; \
+_method(const char *aString)                   \
+{                                              \
+    if (_member) PR_Free(_member);             \
+    if (!aString)                              \
+      _member = nsnull;                        \
+    else if (!(_member = PL_strdup(aString)))  \
+      return NS_ERROR_OUT_OF_MEMORY;           \
+    return NS_OK;                              \
 }
 
 /* Getter/Setter macros.