<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><blockquote type="cite" class="">On May 18, 2017, at 10:20 AM, René J.V. Bertin via cfe-dev <<a href="mailto:cfe-dev@lists.llvm.org" class="">cfe-dev@lists.llvm.org</a>> wrote:<br class=""></blockquote><div><blockquote type="cite" class=""><div class=""><br style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><span style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">To make matters even more complex: on Mac the situation is the opposite, that is clang always uses a sincos library function provided by Apple.</span></div></blockquote><br class=""></div><div>Right; Apple’s libm does not ever set `errno`, and defines math_errhandling to MATH_ERREXCEPT, so we don’t need to worry about `errno` on Apple platforms; further our `sincos` produces the same result as separate calls to `sin` and `cos` do, so this transform never perturbs observable results.</div><div class=""><br class=""></div><div class="">– Steve</div></body></html>