segmentation faults

[Wyles Eric - ewyles]

Hello,   This is a lengthy explanation but please stay with me. I’m hoping someone can help me track down some segmentation faults we have been experiencing with log4cxx.   We are using one of the daily tar files from littletux.org. The file  we pulled was from sometime around Oct 25, 2005. Here is the version info from the build.xml:               build.xml:<property name="version" value="0.9.8"/>             build.xml:<property name="apr.version" value="1.2.2"/>             build.xml:<property name="aprutil.version" value="1.2.2"/>             build.xml:<property name="cppunit.version" value="1.10.2"/>               We have made some slight modifications to the source to get a SocketAppender up and running. We just had to implement the LoggingEvent::write() method so that it would write to the output stream using the format that our logging server expects.   This is a multi-threaded application running on RHEL 3 compiled under gcc. Here is the output of gcc -v:               [EMAIL PROTECTED] ewyles]$ gcc -v             Reading specs from  /usr/lib/gcc-lib/i386-redhat-linux/3.2.3/specs             Configured with: ../configure --prefix=/usr  --mandir=/usr/share/man --        infodir=/usr/share/info --enable-shared  --enable-threads=posix --          disable-checking --with-system-zlib  --enable-__cxa_atexit --host=i386-         redhat-linux             Thread model: posix             gcc version 3.2.3 20030502 (Red Hat Linux 3.2.3-47)   In our code, we declare loggers in 3 different ways.   1 – We have a global logger in a file called ‘logger.cpp’: log4cxx::LoggerPtr logger(log4cxx::Logger::getLogger(“<application_name>”));          We have a header file called ‘logging.h’ that is included by all other source files in our project:             extern LoggerPtr logger;   2 – Each class in our project has a logger as a private member variable. In the class header file:               class <class_name> { private:                         static LoggerPtr logger; }   And then in the .cpp file for the class we do this:   LoggerPtr <class_name>::logger(Logger::getLogger("<application_name>.<class_name>"));   3 – Each method of each class has a locally declared logger. In the .cpp file for the class, each method looks like this:   short <class_name>::<method_name>() {                         static LoggerPtr logger(Logger::getLogger("<application_name>.<class_name>.<method_name>"));                           //logic for the class goes here }   The idea is that each method in our application will have a logger called application.class.method and that we can set the logging level for the application as a whole or fine tune it at the class and/or method levels for debugging.   Now for the actual problem. Once in a while, our application crashes with a segmentation fault. The stack trace looks like this:   Received signal 11 (Segmentation fault) from process [4] Stack Trace:    0 : <application_name>(_ZN14clsApplication18FatalSignalHandlerEiP7siginfoPv+0x27e) [0x80fc050]    1 : /lib/tls/libpthread.so.0 [0xf93e50]    2 : /usr/local/hive/i386/ags/lib/liblog4cxx.so(_ZN7log4cxx9Hierarchy9getLoggerERKSsRKNS_7helpers10ObjectPtrTINS_3spi13LoggerFactoryEEE+0x251) [0x608a09]    3 : /usr/local/hive/i386/ags/lib/liblog4cxx.so(_ZN7log4cxx9Hierarchy9getLoggerERKSs+0x39) [0x6087ab]    4 : /usr/local/hive/i386/ags/lib/liblog4cxx.so(_ZN7log4cxx10LogManager9getLoggerERKSs+0x3c) [0x57528a]    5 : /usr/local/hive/i386/ags/lib/liblog4cxx.so(_ZN7log4cxx6Logger9getLoggerEPKc+0x53) [0x6063b9]    6-14 : <various classes specific to our application>    15 : /lib/tls/libpthread.so.0 [0xf8ddec]    16 : /lib/tls/libc.so.6(__clone+0x5a) [0xb9da2a]     There are 2 times we have seen this occur. Most frequently, it happens when the application is attempting to start up. We create several thread on startup and once in a while we will get this segmentation fault. The other case where we have seen this is after the application has been running for a while, but needs to create more threads. Once in a while if we are creating many threads for some purpose, we will get this segmentation fault. It could be coincidence, but it seems that in both cases where we run into this error it is during times when we are creating threads.   Does anyone have any ideas or suggestions? I have a gcc disassembly of our _ZN7log4cxx9Hierarchy9getLoggerERKSsRKNS_7helpers10ObjectPtrTINS_3spi13LoggerFactoryEEE method if that would be useful to anyone.   Log4cxx is working great for us, we just need to figure out how to get around this segmentation fault! ************************************************************************* The information contained in this communication is confidential, is intended only for the use of the recipient named above, and may be legally privileged. 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