diff options
| -rw-r--r-- | libstdc++-v3/ChangeLog | 4 | ||||
| -rw-r--r-- | libstdc++-v3/libsupc++/guard.cc | 30 |
2 files changed, 19 insertions, 15 deletions
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 2f5b103..f1941cb 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,3 +1,7 @@ +2011-05-26 Jonathan Wakely <jwakely.gcc@gmail.com> + + * libsupc++/guard.cc: Fix comments. + 2011-05-25 Ian Lance Taylor <iant@google.com> PR libstdc++/49060 diff --git a/libstdc++-v3/libsupc++/guard.cc b/libstdc++-v3/libsupc++/guard.cc index 6e3d415..7514fa4 100644 --- a/libstdc++-v3/libsupc++/guard.cc +++ b/libstdc++-v3/libsupc++/guard.cc @@ -85,7 +85,7 @@ namespace # if defined(__GTHREAD_HAS_COND) && !defined(_GLIBCXX_USE_FUTEX) namespace { - // A single conditional variable controlling all static initializations. + // A single condition variable controlling all static initializations. static __gnu_cxx::__cond* static_cond; // using a fake type to avoid initializing a static class. @@ -136,7 +136,7 @@ __set_and_release (__cxxabiv1::__guard *g) #endif /* __GTHREADS */ // -// Here are C++ run-time routines for guarded initiailization of static +// Here are C++ run-time routines for guarded initialization of static // variables. There are 4 scenarios under which these routines are called: // // 1. Threads not supported (__GTHREADS not defined) @@ -147,24 +147,24 @@ __set_and_release (__cxxabiv1::__guard *g) // // The old code supported scenarios 1-3 but was broken since it used a global // mutex for all threads and had the mutex locked during the whole duration of -// initlization of a guarded static variable. The following created a dead-lock -// with the old code. +// initialization of a guarded static variable. The following created a +// dead-lock with the old code. // // Thread 1 acquires the global mutex. // Thread 1 starts initializing static variable. // Thread 1 creates thread 2 during initialization. -// Thread 2 attempts to acuqire mutex to initialize another variable. +// Thread 2 attempts to acquire mutex to initialize another variable. // Thread 2 blocks since thread 1 is locking the mutex. // Thread 1 waits for result from thread 2 and also blocks. A deadlock. // -// The new code here can handle this situation and thus is more robust. Howere, -// we need to use the POSIX thread conditional variable, which is not supported +// The new code here can handle this situation and thus is more robust. However, +// we need to use the POSIX thread condition variable, which is not supported // in all platforms, notably older versions of Microsoft Windows. The gthr*.h // headers define a symbol __GTHREAD_HAS_COND for platforms that support POSIX -// like conditional variables. For platforms that do not support conditional +// like condition variables. For platforms that do not support condition // variables, we need to fall back to the old code. -// If _GLIBCXX_USE_FUTEX, no global mutex or conditional variable is used, +// If _GLIBCXX_USE_FUTEX, no global mutex or condition variable is used, // only atomic operations are used together with futex syscall. // Valid values of the first integer in guard are: // 0 No thread encountered the guarded init @@ -211,7 +211,7 @@ namespace __cxxabiv1 #endif } - // acuire() is a helper function used to acquire guard if thread support is + // acquire() is a helper function used to acquire guard if thread support is // not compiled in or is compiled in but not enabled at run-time. static int acquire(__guard *g) @@ -284,7 +284,7 @@ namespace __cxxabiv1 { // The guarded static is currently being initialized by // another thread, so we release mutex and wait for the - // conditional variable. We will lock the mutex again after + // condition variable. We will lock the mutex again after // this. get_static_cond().wait_recursive(&get_static_mutex()); } @@ -295,7 +295,7 @@ namespace __cxxabiv1 } # else // This provides compatibility with older systems not supporting - // POSIX like conditional variables. + // POSIX like condition variables. if (acquire(g)) { mw.unlock = false; @@ -335,7 +335,7 @@ namespace __cxxabiv1 set_init_in_progress_flag(g, 0); // If we abort, we still need to wake up all other threads waiting for - // the conditional variable. + // the condition variable. get_static_cond().broadcast(); return; } @@ -344,7 +344,7 @@ namespace __cxxabiv1 set_init_in_progress_flag(g, 0); #if defined(__GTHREADS) && !defined(__GTHREAD_HAS_COND) // This provides compatibility with older systems not supporting POSIX like - // conditional variables. + // condition variables. if (__gthread_active_p ()) static_mutex->unlock(); #endif @@ -385,7 +385,7 @@ namespace __cxxabiv1 #if defined(__GTHREADS) && !defined(__GTHREAD_HAS_COND) // This provides compatibility with older systems not supporting POSIX like - // conditional variables. + // condition variables. if (__gthread_active_p()) static_mutex->unlock(); #endif |