[lldb-dev] [PATCH] Typo in ProcessMonitor::WaitForInitialTIDStop? for linux

[Matthew Gardiner]

Hi,

I'm trying to discover why a tracer stop gets reported as process exit
by 32-bit linux lldb. I happened upon this piece of code:

bool
ProcessMonitor::WaitForInitialTIDStop(lldb::tid_t tid)
{
     Log *log (ProcessPOSIXLog::GetLogIfAllCategoriesSet (POSIX_LOG_PROCESS));
     if (log)
         log->Printf ("ProcessMonitor::%s(%" PRIu64 ") waiting for thread to stop...", __FUNCTION__, tid);

     // Wait for the thread to stop
     while (true)
     {
         int status = -1;
         if (log)
             log->Printf ("ProcessMonitor::%s(%" PRIu64 ") waitpid...", __FUNCTION__, tid);
         lldb::pid_t wait_pid = waitpid(tid, &status, __WALL);
         if (status == -1)
         {
             // If we got interrupted by a signal (in our process, not the
             // inferior) try again.
             if (errno == EINTR)
                 continue;

Surely this line is wrong "if (status == -1)" ?? We should checking the
return value of waitpid not the optional status field.

Patch attached.

Index: source/Plugins/Process/Linux/ProcessMonitor.cpp
===================================================================
--- source/Plugins/Process/Linux/ProcessMonitor.cpp	(revision 201779)
+++ source/Plugins/Process/Linux/ProcessMonitor.cpp	(working copy)
@@ -1700,7 +1700,7 @@
          if (log)
              log->Printf ("ProcessMonitor::%s(%" PRIu64 ") waitpid...", __FUNCTION__, tid);
          lldb::pid_t wait_pid = waitpid(tid, &status, __WALL);
-        if (status == -1)
+        if (-1 == wait_pid)
          {
              // If we got interrupted by a signal (in our process, not the
              // inferior) try again.


thanks
Matt


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