[ http://issues.apache.org/jira/browse/XERCESC-1392?page=comments#action_62173 ] Fred Dushin commented on XERCESC-1392: --------------------------------------
> Hi, does this mean you think there is a bug in the default scanner? > Unfortnatly we cant use things like const_cast or the standard > library due to portability reasons. I think the default scanner is okay. Or, at least I could not reproduce the error with anything but the WF scanner. That's not to say there could be other lingering bugs in the other scanners, but they otherwise seem fairly well behaved. I haven't spent much time looking at the WF scanner, but I did see some traditional C-style casts, which I suppose could result in some stack corruption. If I have a chance, I'll try replacing these traditional casts with modern ones, and see if this addresses the problem. Maybe we could define macros that could address this for mordern compilers? E.g., something along the lines of #ifdef XERCESC_HAS_MODERN_CAST #define XERCESC_CONST_CAST( type, expr ) const_cast< type >( expr ) #define XERCESC_STATIC_CAST( type, expr ) static_cast< type >( expr ) ... #else #define XERCESC_CONST_CAST( type, expr ) ((type)( expr )) #define XERCESC_STATIC_CAST( type, expr ) ((type)( expr )) ... #fi One thing I did not mention was that I could reproduce this with the 2.6 binaries, as well, so it should be fairly easy to replicate. > Bus Error using XMLUni::fgWFXMLScanner on 64 bit Solaris > -------------------------------------------------------- > > Key: XERCESC-1392 > URL: http://issues.apache.org/jira/browse/XERCESC-1392 > Project: Xerces-C++ > Type: Bug > Components: Non-Validating Parser > Versions: 2.6.0 > Environment: > uname -a > SunOS fu 5.8 Generic_108528-29 sun4u sparc SUNW,Ultra-4 > > CC -V > CC: Sun C++ 5.5 2003/03/12 > Reporter: Fred Dushin > > Readily reproducible bus error using the Well-Formedness XML Scanner > (XMLUni::fgWFXMLScanner) on 64 bit Solaris. This does not appear to occur in > 32 bit mode. Not able to reproduce this error with the other XML scanners. > Used Sun C++ 5.5, and reproduced on Xerces 2.4 and 2.6, as well as with > Forte6 (Update 2). > The Bus Error is as the result on an address alignment error, when any > exception is thrown from a SAX2 handler. The C++ runtime appears to be > peeking up the stack for a frame to catch the exception, when the bus error > occurs. > Below is a patch file for the 2.6 SAX2Count sample program. This patch > modifies the SAXCount driver to use the WF XML scanner, and the handler to > always throw an exception. > Here is a stacktrace, from dbx: > [EMAIL PROTECTED] ([EMAIL PROTECTED]) terminated by signal BUS (invalid > address alignment) > 0xffffffff7e007340: exception_matches : ld [%o1 + 0x28], %o3 > (dbx) where -h > current thread: [EMAIL PROTECTED] > =>[1] __Cimpl::exception_matches(0xffffffff7e3f3920, 0x270022, > 0x8000000000000000, 0x0, 0x9e8, 0x0), at 0xffffffff7e007340 > [2] __Cimpl::locate_handler_frame(0x1, 0x1000041f4, 0x0, > 0xffffffff7ef617b8, 0xffffffff7f167d08, 0xffffffff7e10d580), at > 0xffffffff7e005cf4 > [3] __Crun::ex_throw(0xffffffff7e10d580, 0xffffffff7e3f3920, 0x0, 0x10342c, > 0xffffffff7e24ad68, 0x100107ae0), at 0xffffffff7e005e28 > [4] SAX2CountHandlers::startElement(0xffffffff7fffd698, 0x1, 0x103970, > 0xffffffff7eebd820, 0x0, 0x100107ae0), at 0x1000041e4 > [5] xercesc_2_6::SAX2XMLReaderImpl::startElement(0x1001309a8, 0x100131fc8, > 0x1, 0x10012f950, 0x100004f08, 0x0), at 0xffffffff7ee3328c > [6] xercesc_2_6::WFXMLScanner::scanStartTagNS(0x100137e38, 0x0, 0x0, > 0x100131fc8, 0x0, 0x1), at 0xffffffff7ee9c6a4 > [7] xercesc_2_6::WFXMLScanner::scanContent(0x100137e38, 0x1, 0x1, 0x0, > 0xe7, 0xffffffff7fffcc80), at 0xffffffff7ee9ae1c > [8] xercesc_2_6::WFXMLScanner::scanDocument(0x100137e38, 0x1, 0x0, > 0xffffffff7f15f0e0, 0x0, 0x10010b370), at 0xffffffff7ee99b58 > [9] xercesc_2_6::XMLScanner::scanDocument(0x100137e38, 0xffffffff7ee99ad8, > 0x10010b370, 0x226b70, 0xffffffff7f167e38, 0x10010c718), at 0xffffffff7eebae20 > [10] xercesc_2_6::XMLScanner::scanDocument(0x100137e38, 0xffffffff7fffdb5a, > 0x19, 0x1000038a8, 0x3, 0x100109840), at 0xffffffff7eebb1a4 > [11] xercesc_2_6::SAX2XMLReaderImpl::parse(0x1001309a8, 0x0, 0x1050c5dbaf, > 0xffffffffffffffc0, 0xfffffffffffffff8, 0x1093122440), at 0xffffffff7ee32694 > [12] main(0x102f9fb79c8, 0x3e8, 0xffffffff7fffd180, 0xffffffff7fffd568, > 0xffffffff7fffd698, 0x100107ae0), at 0x1000038a8 > Patch: > diff -r -c SAX2Count.ORIG/SAX2Count.cpp SAX2Count/SAX2Count.cpp > *** SAX2Count.ORIG/SAX2Count.cpp Thu Mar 31 13:29:32 2005 > --- SAX2Count/SAX2Count.cpp Thu Mar 31 13:29:37 2005 > *************** > *** 302,307 **** > --- 302,311 ---- > parser->setFeature(XMLUni::fgXercesSchemaFullChecking, > schemaFullChecking); > parser->setFeature(XMLUni::fgXercesIdentityConstraintChecking, > identityConstraintChecking); > parser->setFeature(XMLUni::fgSAX2CoreNameSpacePrefixes, > namespacePrefixes); > + parser->setProperty( > + XMLUni::fgXercesScannerName, > + const_cast<unsigned short*const>(XMLUni::fgWFXMLScanner) > + ); > > if (valScheme == SAX2XMLReader::Val_Auto) > { > diff -r -c SAX2Count.ORIG/SAX2CountHandlers.cpp > SAX2Count/SAX2CountHandlers.cpp > *** SAX2Count.ORIG/SAX2CountHandlers.cpp Thu Mar 31 13:29:33 2005 > --- SAX2Count/SAX2CountHandlers.cpp Thu Mar 31 13:29:41 2005 > *************** > *** 74,79 **** > --- 74,80 ---- > { > fElementCount++; > fAttrCount += attrs.getLength(); > + throw std::logic_error( "crash me!" ); > } > > void SAX2CountHandlers::characters( const XMLCh* const chars -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - If you want more information on JIRA, or have a bug to report see: http://www.atlassian.com/software/jira --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
