Hi,<div><br></div><div>LLVM classifies _Znwm as a builtin by default. After some discussion, the C++ core working group have decreed that that is not correct: calls to "operator new" *can* be optimized, but only if they come from new-expressions, and not if they come from explicit calls to ::operator new. We cannot work around this in the frontend by marking the call as 'nobuiltin' for two reasons:</div>
<div><br></div><div>1) The 'nobuiltin' attribute doesn't actually prevent the optimization (see recent patch on llvmcommits)</div><div>2) We can't block the optimization if the call happens through a function pointer, unless we also annotate all calls through function pointers as 'nobuiltin'</div>
<div><br></div><div>How feasible would it be to make the 'builtin-ness' of _Znwm etc be opt-in rather than opt-out? Is there some other option we could pursue?</div>