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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Hi,<br><br>I have a trivial case where the Static Analyzer is not catching a double free bug:<br><br><o:p></o:p></p><p class=MsoNormal>==============<br> char *s;<o:p></o:p></p><p class=MsoNormal> for(int i = 0; <b><u>i < 4</u></b>; i++)<o:p></o:p></p><p class=MsoNormal> {<o:p></o:p></p><p class=MsoNormal> s = (char*)malloc(10);<o:p></o:p></p><p class=MsoNormal> free(s);<o:p></o:p></p><p class=MsoNormal> }<o:p></o:p></p><p class=MsoNormal> free(s);<o:p></o:p></p><p class=MsoNormal>================<o:p></o:p></p><p class=MsoNormal>However, if I change the code to:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>==============<br> char *s;<o:p></o:p></p><p class=MsoNormal> for(int i = 0; <b><u>i < 3</u></b>; i++)<o:p></o:p></p><p class=MsoNormal> {<o:p></o:p></p><p class=MsoNormal> s = (char*)malloc(10);<o:p></o:p></p><p class=MsoNormal> free(s);<o:p></o:p></p><p class=MsoNormal> }<o:p></o:p></p><p class=MsoNormal> free(s);<o:p></o:p></p><p class=MsoNormal>================<o:p></o:p></p><p class=MsoNormal>A double free warning is thrown.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>On exploring this further, I noticed that the function MallocChecker::FreeMemAux is called no more than 4 times. Ie: I can place as many “free(s)” after the last one in the first code chunk and it will never be caught.<o:p></o:p></p><p class=MsoNormal>Its calling method MallocChecker::CheckPostStmt seems to be limited to being called a maximum of 8 times.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is there a threshold set on the number of times a checker can be called? If so, can that be tweaked?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks in advance!<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Regards,<o:p></o:p></p><p class=MsoNormal>Nikhil<o:p></o:p></p></div></body></html>