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<TITLE>RE: [LCP]Segmentation Faults when calling free()</TITLE>
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<P><FONT SIZE=2>> Solution? Compile with electric fence, and run in a debugger. Efence</FONT>
<BR><FONT SIZE=2>> causes a segfault on the first instruction which writes </FONT>
<BR><FONT SIZE=2>> outside the n bytes</FONT>
<BR><FONT SIZE=2>> which you've been specifically allocated (and hence catches overruns,</FONT>
<BR><FONT SIZE=2>> underruns, and fencepost errors). Very, very useful for </FONT>
<BR><FONT SIZE=2>> finding bugs like</FONT>
<BR><FONT SIZE=2>> this.</FONT>
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<P><FONT SIZE=2>Just be aware that since efence aligns the memory to change page</FONT>
<BR><FONT SIZE=2>where the allocated space ends, you'll have to do at least two runs,</FONT>
<BR><FONT SIZE=2>once to detect overruns, and another to detect underruns (as in each</FONT>
<BR><FONT SIZE=2>it will align differently, either the end of a block on the end of</FONT>
<BR><FONT SIZE=2>a page, or the beginning of a block to the beginning of a page).</FONT>
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<P><FONT SIZE=2>There is also Valgrind, which runs your program in a virtual CPU,</FONT>
<BR><FONT SIZE=2>keeping track of what is yours and what is not.</FONT>
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<P><FONT SIZE=2>Sorry for the HTML, it leaves in plain text but is converted by</FONT>
<BR><FONT SIZE=2>our company's (MS) mail server.</FONT>
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<P><FONT SIZE=2>-- </FONT>
<BR><FONT SIZE=2>Vincent Penquerc'h </FONT>
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