Fix termination on MinGW/Cygwin by calling Windows API to terminate. #636
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MinGW and Cygwin do not allow Async break to occur without user intervention. The problem is with -exec-abort (stop debugging) while in run mode requires us to do an async break so that we can abort. Since we can't do that without additional user intervention, we will terminate the child process instead.
src/MICore/Debugger.cs
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| // to terminate debugging. | ||
| if ((this.IsCygwin || this.IsMinGW) && _debuggeePids.Count > 0) | ||
| { | ||
| int debuggeePid = _debuggeePids.First().Value; |
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_debuggeePids [](start = 42, length = 13)
Is there a reason you only pick the first?
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@gregg-miskelly I took the code from CmdBreakInternal() (line 697) that breaks on the first thread. Would it be better to iterate through the list and terminate each individual item?
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That is what I would have thought, but @paulmaybee would be more familiar with the child process code. Maybe there is a reason that isn't needed.
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Doesn't hurt to terminate all pids. Normally having more than one is a transient state. However there is a non-trivial amount of work done by gdb in between reporting that a new process is available and detaching so that vs can reattach separate miengine instance. If something goes wrong/hangs then killing all children is most likely the right way to recover.
src/MICore/Debugger.cs
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| finally | ||
| { | ||
| if (handle != IntPtr.Zero) | ||
| Marshal.FreeCoTaskMem(handle); |
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FreeCoTaskMem [](start = 40, length = 13)
You need to P/Invoke to CloseHandle
src/MICore/Debugger.cs
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| // the normal path of sending an internal async break so we can exit doesn't work. | ||
| // Therefore, we will call TerminateProcess on the debuggee with the exit code of 0 | ||
| // to terminate debugging. | ||
| if ((this.IsCygwin || this.IsMinGW) && _debuggeePids.Count > 0) |
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) [](start = 82, length = 1)
Exclude gdbserver cases?
src/MICore/Debugger.cs
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| public static extern IntPtr OpenProcess(int dwDesiredAccess, [MarshalAs(UnmanagedType.Bool)] bool bInheritHandle, int dwProcessId); | ||
| [DllImport("kernel32.dll", SetLastError = true)] | ||
| [return: MarshalAs(UnmanagedType.Bool)] | ||
| static extern bool TerminateProcess(IntPtr hProcess, uint uExitCode); |
MinGW and Cygwin do not allow Async break to occur without user
intervention. The problem is with -exec-abort (stop debugging) while in
run mode requires us to do an async break so that we can abort. Since we
can't do that without additional user intervention, we will terminate
the child process instead.