On 04/01/2019 17:38, Florian Weimer via lldb-dev wrote:
Consider this example program:#include <err.h> #include <sys/wait.h> #include <unistd.h> #include <lldb/API/SBDebugger.h> #include <lldb/API/SBProcess.h> #include <lldb/API/SBTarget.h> int main(void) { // Target process for the debugger. pid_t pid = fork(); if (pid < 0) err(1, "fork"); if (pid == 0) while (true) pause(); lldb::SBDebugger::Initialize(); { auto debugger(lldb::SBDebugger::Create()); if (!debugger.IsValid()) errx(1, "SBDebugger::Create failed"); auto target(debugger.CreateTarget(nullptr)); if (!target.IsValid()) errx(1, "SBDebugger::CreateTarget failed"); lldb::SBAttachInfo attachinfo(pid); lldb::SBError error; auto process(target.Attach(attachinfo, error)); if (!process.IsValid()) errx(1, "SBTarget::Attach failed: %s", error.GetCString()); error = process.Detach(); if (error.Fail()) errx(1, "SBProcess::Detach failed: %s", error.GetCString()); } lldb::SBDebugger::Terminate(); if (kill(pid, SIGKILL) != 0) err(1, "kill"); if (waitpid(pid, NULL, 0) < 0) err(1, "waitpid"); return 0; } Run it in a loop like this: $ while ./test-attach ; do date; done On Linux x86-64 (Fedora 29), with LLDB 7 (lldb-7.0.0-1.fc29.x86_64) and kernel 4.19.12 (kernel-4.19.12-301.fc29.x86_64), after 100 iterations or so, attaching to the newly created process fails: test-attach: SBTarget::Attach failed: lost connection This also reproduces occasionally with LLDB itself (with “lldb -p PID”). Any suggestions how to get more information about the cause of this error?
I would recommend enabling gdb-remote logging (so something like: debugger.HandleCommand("log enable gdb-remote packets")) to see at which stage do we actually lose the gdb-server connection.
My best bet would be that on your machine/build the server is slower than usual in responding to one of the client packets and that causes the connection to be dropped.
cheers, pavel _______________________________________________ lldb-dev mailing list lldb-dev@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-dev
