<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Jay, I think your usage of TInt and TWord is strongly at odds with its intended use. Certainly, allowing TInt.Add/Subtract to overflow will break large swaths of the front-end. There is a deep contract there that requires that TInt arithmetic not provide bogus results.<div><br></div><div><br><div>
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<br><div><div>On 10 Feb 2010, at 12:58, Jay Krell wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>CVSROOT:<span class="Apple-tab-span" style="white-space:pre"> </span>/usr/cvs<br>Changes by:<span class="Apple-tab-span" style="white-space:pre"> </span>jkrell@birch.<span class="Apple-tab-span" style="white-space:pre"> </span>10/02/10 12:58:11<br><br>Modified files:<br><span class="Apple-tab-span" style="white-space:pre"> </span>cm3/m3-sys/m3back/src/: Stackx86.m3 <br><br>Log message:<br><span class="Apple-tab-span" style="white-space:pre"> </span>allow negating FIRST(INTEGER) even though it overflows<br><span class="Apple-tab-span" style="white-space:pre"> </span>allows this test case to compile:<br><span class="Apple-tab-span" style="white-space:pre"> </span>C:\dev2\cm3.2\m3-sys\m3tests\src\p1\p137>cm3<br><span class="Apple-tab-span" style="white-space:pre"> </span>--- building in NT386 ---<br><span class="Apple-tab-span" style="white-space:pre"> </span><br><span class="Apple-tab-span" style="white-space:pre"> </span>new source -> compiling Main.m3<br><span class="Apple-tab-span" style="white-space:pre"> </span>"..\Main.m3", line 35: doneg: Negate overflowed<br><span class="Apple-tab-span" style="white-space:pre"> </span>1 error encountered<br><span class="Apple-tab-span" style="white-space:pre"> </span>compilation failed => not building program "pgm.exe"<br><span class="Apple-tab-span" style="white-space:pre"> </span>Fatal Error: package build failed<br><span class="Apple-tab-span" style="white-space:pre"> </span><br><span class="Apple-tab-span" style="white-space:pre"> </span>tempting to make TInt.Add/Subtract return the value<br><span class="Apple-tab-span" style="white-space:pre"> </span>even if overflow, but for now, no.<br><span class="Apple-tab-span" style="white-space:pre"> </span>This fix assumes two's complement, that is,<br><span class="Apple-tab-span" style="white-space:pre"> </span>it assumes FIRST(INTEGER) = -FIRST(INTEGER)<br></div></blockquote></div><br></div></body></html>