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<h2>digitalmars.D.bugs - optimizer bug</h2> <div id="PostingTOC"> <ul> <li> <a href="#N4766"> xs0</a> (6/6) Aug 11 2005 If the attached code is compiled without -o, it works fine; when </li> <ul> <li> <a href="#N4768"> xs0</a> (24/24) Aug 11 2005 Well, I did manage to make it shorter :) I was using constants, and they... </li> </ul> </ul> </div> <div id="Posting"><div id="PostingHeading"><a name="N4766"> <a href="#N4768">reply</a> xs0 <xs0 xs0.com> <a href="https://www.digitalmars.com/pnews/read.php?server=news.digitalmars.com&group=digitalmars.D.bugs&artnum=4766"> writes</a>:</a> </div> <pre> If the attached code is compiled without -o, it works fine; when optimized, however, it always produces -nan (regardless of the actual coordinates used). If I change all doubles to reals, it also works fine.. Sorry there's so much code, I couldn't make it shorter while maintaining the bug. The problem is in the line starting with "double tmp=...". xs0 </pre> <div id="PostingFooting"> Aug 11 2005 </div> </div><div id="Posting"><div id="PostingHeading"><a name="N4768"> <a href="#N4766">parent</a> xs0 <xs0 xs0.com> <a href="https://www.digitalmars.com/pnews/read.php?server=news.digitalmars.com&group=digitalmars.D.bugs&artnum=4768"> writes</a>:</a> </div> <pre> Well, I did manage to make it shorter :) I was using constants, and they obviously got folded during compilation.. The code below exhibits the same problem.. Again, changing doubles to reals makes it work.. ---- import std.stdio; import std.math; import std.random; void main() { double x10=rand()*0.000001; double x11=rand()*0.000001; double x20=rand()*0.000001; double x21=rand()*0.000001; double y10=rand()*0.000001; double y11=rand()*0.000001; double y20=rand()*0.000001; double y21=rand()*0.000001; double tmp=(x10*x10 + x11*x11 + x20*x20 + x10*(x11 - 2.0*x20 - x21) + x20*x21 + x21*x21 - x11*(x20 + 2.0*x21) + y10*y10 + y10*y11 + y11*y11 - 2.0*y10*y20 - y11*y20 + y20*y20 - y10*y21 - 2.0*y11*y21 + y20*y21 + y21*y21); writefln(tmp); } xs0 </pre> <div id="PostingFooting"> Aug 11 2005 </div> </div> <div id="footer_ad"> <br><br><br><br> </div> </div></div><div class="naked_ctrl"> <form action="/index.cgi/speech" method="get" name="gate"> <p><a href="http://altstyle.alfasado.net">AltStyle</a> によって変換されたページ <a href="https://digitalmars.com/d/archives/digitalmars/D/bugs/4766.html">(->オリジナル)</a> / <label>アドレス: <input type="text" name="naked_post_url" value="https://digitalmars.com/d/archives/digitalmars/D/bugs/4766.html" size="22" /></label> <label>モード: <select name="naked_post_mode"> <option value="default">デフォルト</option> <option value="speech" selected="selected">音声ブラウザ</option> <option value="ruby">ルビ付き</option> <option value="contrast">配色反転</option> <option value="larger-text">文字拡大</option> <option value="mobile">モバイル</option> </select> <input type="submit" value="表示" /> </p> </form> </div> </body></html>