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[[!tag open_issue_glibc open_issue_libpthread]]

libpthread: glibc 44e2ad5ab8c21dbfed3e384ba2ed31d7a8fc4744
998e5fc14595229101561d76282036839e5b66ab -- The robust mutex functions are in
POSIX 2008.

---

IRC, #hurd, unknown date.

    <youpi> neal: bad news: you remember the PTHREAD_RECURSIVE_MUTEX_INITIALIZER that points to a global __pthread_recursive_mutexattr?
    <youpi> that doesn't work
    <youpi> because some libraries like libstdc++ do not link against libpthread, while still using pthread_mutex_lock/unlock (counting on them being provided by either libc or libpthread-stubs)
    <CIA-1> sthibaul-guest * r626 pkg-hurd/hurd/trunk/debian/ (changelog patches/series): 
    <CIA-1> * debian/patches/libpthread_rwlock_initializer.patch: Disable patch for now:
    <CIA-1> our initializer does not work when the application does not link against
    <CIA-1> libpthread.

    <CIA-1> sthibaul-guest * r629 pkg-hurd/hurd/trunk/debian/ (changelog patches/series): do not disable adding PTHREAD_RWLOCK_INITIALIZER, that's not the one that poses problems
    <CIA-1> sthibaul-guest * r630 pkg-hurd/hurd/trunk/debian/ (3 files in 2 dirs): 
    <CIA-1> * debian/patches/libpthread_no_recursive_mutex_initializer.patch: New patch
    <CIA-1> to drop undefined references to __pthread_recursive_mutexattr.

    <youpi> I'm thinking about how to fix the PTHREAD_RECURSIVE_MUTEX_INITIALIZER
    <youpi> instead of a pointer to a static attribute variable, which posed problem
    <youpi> could we perhaps consider that page 0 is never mapped
    <youpi> and thus not only pointer 0 but also 1 2, etc. are invalid
    <neal> I think that is a good solution
    <youpi> and use them as special values
    <neal> alternatively, we could assume that -PAGESIZE is never valid
    <youpi> that makes us test it in all pthread_mutex_* functions, but it's not so bad
    <neal> I'm not sure which is better
    <youpi> why isn't it?
    <neal> because the kernel is mapped there normally
    <youpi> the kernel could be elsewhere
    <neal> true
    <youpi> in a 64bit adressing space for instance
    <neal> I think your solution is a good one
    <youpi> ok

    <CIA-1> sthibault * r633 pkg-hurd/hurd/trunk/debian/ (3 files in 2 dirs): 
    <CIA-1> * debian/patches/libpthread_recursive_mutex_initializer.patch: New patch
    <CIA-1> to fix the recursive mutex initializers usage in libraries not linking
    <CIA-1> against libpthread.