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</o:shapelayout></xml><![endif]--></head><body bgcolor=white lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:windowtext'>I am compiling with the Text IDE, and I set it up with the same settings I was using with the 32bit version… and yes I did turn on Range checking, so that explains why we didn’t notice it before.<o:p></o:p></span></p><p class=MsoNormal><span style='color:windowtext'><o:p> </o:p></span></p><div><p class=MsoNormal><span style='color:windowtext'>James<o:p></o:p></span></p></div><p class=MsoNormal><span style='color:windowtext'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='color:windowtext'>From:</span></b><span style='color:windowtext'> fpc-pascal <fpc-pascal-bounces@lists.freepascal.org> <b>On Behalf Of </b>Jean SUZINEAU<br><b>Sent:</b> Friday, August 9, 2019 12:34 AM<br><b>To:</b> James Richters <james@productionautomation.net>; 'FPC-Pascal users discussions' <fpc-pascal@lists.freepascal.org><br><b>Subject:</b> Re: [fpc-pascal] USB Human Interface Devices<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hi James,<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Le 09/08/2019 à 02:19, James Richters a écrit :<o:p></o:p></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><pre>so this was strange... it was working before<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>line 81 For J := 1 to Length(PortPath)-1 do<o:p></o:p></pre><pre>line 82 Write('->',PortPath[I]);<o:p></o:p></pre><pre><o:p> </o:p></pre><pre>Line 82 is using variable I but it's in a loop that uses J, I didn't think that made a lot of sense.. so without really analyzing how any of this was supposed to work.. I just changed the I to a J and then I got this:<o:p></o:p></pre></blockquote><p>I think it's a typo. <o:p></o:p></p><p>I think we didn't saw it before because Range type checking was disabled ( <span class=cmsy-10>{</span><span class=cmtt-10>$RANGECHECKS OFF</span><span class=cmsy-10>} </span>or {$R-} ). <o:p></o:p></p><p>It seems it's the default value for the compiler: <a href="https://www.freepascal.org/docs-html/prog/progsu65.html">https://www.freepascal.org/docs-html/prog/progsu65.html</a> . Very often in Windows system functions you have to deal with records with declared with a length of 1 and the real length stored a few bytes before in the record. This could not work with {$R+} <o:p></o:p></p><p>But it's seems that for some reason it's enabled for your compiler (may be a different default value when your recompiled with fpcupdeluxe, or more likely a different default value in your settings for fp.exe ?).<o:p></o:p></p><p>I'm not an expert in memory allocation, but I think that while a certain amount of memory is allocated after the memory pointed to by PortPath and you're in {$R-} mode, you can happily read several bytes after the actual end of PortPath without any segmentation fault or memory access exception.<o:p></o:p></p><p><o:p> </o:p></p><pre><o:p> </o:p></pre></div></body></html>