Changes between Version 10 and Version 11 of FrequentlyAskedQuestions

01/10/11 11:39:41 (10 years ago)

Explain the latest threading issue


  • FrequentlyAskedQuestions

    v10 v11  
    1313=== I get a lot of errors stating "ERROR: No debug map or DWARF data was found to link." when building on Mac OS X! ===
    1414This appears to be a bug in the dwarfutils - try upgrading Xcode to version 2.5 or later.
     16=== When using libtrace 3.0.7 or 3.0.8, I get a segmentation fault whenever I try to read a trace file! ===
     17There appears to be a nasty threading bug that can crop up when libtrace is built with gcc 4.4.1 (which is the packaged version on many Ubuntu systems).
     19 * The best possible fix (until libtrace 3.0.9 is released) is to make the change described in r1681 and re-build libtrace. Obviously this will involve editing the libtrace source code but will fix the problem without impacting on performance.
     20 * An alternative is to disable threaded IO by running 'export LIBTRACEIO=nothreads' in the terminal which you are using to run the failing libtrace program. This will disable threaded IO, which will make the trace processing slower.
     21 * You could also disable optimisations by adding 'CFLAGS="-g -O0"' when running ./configure - this will mean that you can still use threaded IO but the entirety of libtrace will be unoptimised.