<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><div>On Sep 19, 2011, at 6:51 PM, Anna Zaks wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; ">+ FullSourceLoc genLocation(const ParentMap *PM=0) const;<br>+ PathDiagnosticRange genRange(const ParentMap *PM=0) const;</span></blockquote></div><div><br></div>Hi Anna,<div><br><div>Instead of passing the ParentMap, how about having genLocation() lazily query LocationContext for one? That way it only gets created when we need it.</div></div><div><br></div><div>Actually, it it looks like we are still using the LC member variable in genRange(), instead of the passed ParentMap:</div><div><br></div><div><div> case Stmt::ObjCForCollectionStmtClass: {</div><div> SourceLocation L = getValidSourceLocation(S, LC->getParentMap());</div><div> return SourceRange(L, L);</div></div><div><br></div><div>Since LocationContext isn't guaranteed to live for the lifetime of PathDiagnosticLocation, I suggest:</div><div><br></div><div>1) Remove the LC member variable (fix potential use-after-free).</div><div>2) Pass (possibly null?) LocationContext * to genLocation() and genRange()</div><div>3) Lazily query that LocationContext for a ParentMap as needed. LocationContext (or really, AnalysisContext) will make sure the ParentMap is constructed once.</div><div><br></div><div>What do you think?</div><div><br></div><div>Cheers,</div><div>Ted</div></body></html>