Coverity found this: 621 // This is a header so we need to cache and output later. 622 // Ok, now we will setup the header info for the header array! 5. alloc_fn: Storage is returned from allocation function PR_Calloc. 6. var_assign: Assigning: ptr = storage returned from PR_Calloc(1U, 16U). 623 headerInfoType *ptr = (headerInfoType *) PR_NEWZAP(headerInfoType); 7. Condition ptr, taking true branch 8. Condition tPtr, taking false branch 624 if ( (ptr) && tPtr) 625 { 626 ptr->name = strdup(field); 627 ptr->value = strdup(value); 628 tPtr->AppendElement(ptr); 629 } 630 CID 450203 (#1 of 1): Resource leak (RESOURCE_LEAK)9. leaked_storage: Variable ptr going out of scope leaks the storage it points to. 631 return NS_OK; 632} Observation: this is subtle. On the surface, it may look that |ptr| is put into the list of |tPtr| and all is OK. But it seems that there is a case of |tPtr| being null (after all it is checked for nullness), and in that case |ptr| is not put into any global reference and thus there is a leak! BUG. I think we should put something like the following before 631. if (!tPtr) { PR_FREEIF(ptr); } I also wonder whether we should not return NS_ERROR_UNEXPECTED or somethin in the error case of (!tPtr). At least we can add NS_ENSURE_STATE(tPtr) or something like that to catch strange situation in debug build.