Coverity INTEGER_OVERFLOW - CID 10641

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CID: 10641
Checker: INTEGER_OVERFLOW
Category: critical_argument
CWE definition: http://cwe.mitre.org/data/definitions/190.html
File: /tmp/buildd/nux-2.4.0/NuxCore/TinyXML/tinyxml.cpp
Function: TiXmlDocument::LoadFile(_IO_FILE *, TiXmlEncoding)
Code snippet:
At conditional: "*p == 10" taking False branch
At conditional: "*p == 10" taking False branch
At conditional: "*p == 10" taking True branch
1157 if ( *p == 0xa )
1158 {
1159 // Newline character. No special rules for this. Append all the characters
1160 // since the last string, and include the newline.
CID 10641 - INTEGER_OVERFLOW
Add operation overflows on operands "p - lastPos" and "1L". Example value for operand: "p - lastPos" = 0111111111111111111111111111111111111111111111111111111111111111.
Overflowed or truncated value (or a value computed from an overflowed or truncated value) "p - lastPos + 1L" used as critical argument to function.
1161 data.append ( lastPos, (p - lastPos + 1) ); // append, include the newline
1162 ++p; // move past the newline
1163 lastPos = p; // and point to the new buffer (may be 0)
1164 assert ( p <= (buf + length) );
1165 }
At conditional: "*p == 13" taking False branch
At conditional: "*p == 13" taking False branch
1166 else if ( *p == 0xd )