{"record":{"id":"46cf3da341cec54b","repo":"go-delve/delve","slug":"could-not-find-target-for-thread-d","errorCode":null,"errorMessage":"could not find target for thread %d","messagePattern":"could not find target for thread (.+?)","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"pkg/proc/target_exec.go","lineNumber":100,"sourceCode":"\t\terr := grp.manageUnsatisfiableBreakpoints()\n\t\tif err != nil {\n\t\t\treturn err\n\t\t}\n\n\t\tif grp.cctx.CheckAndClearManualStopRequest() {\n\t\t\tgrp.finishManualStop()\n\t\t\treturn nil\n\t\t}\n\t\tfor _, dbp := range grp.targets {\n\t\t\tdbp.ClearCaches()\n\t\t}\n\t\tlogflags.DebuggerLogger().Debugf(\"ContinueOnce\")\n\t\ttrapthread, stopReason, contOnceErr := grp.procgrp.ContinueOnce(grp.cctx)\n\t\tvar traptgt *Target\n\t\tif trapthread != nil {\n\t\t\ttraptgt = grp.TargetForThread(trapthread.ThreadID())\n\t\t\tif traptgt == nil {\n\t\t\t\treturn fmt.Errorf(\"could not find target for thread %d\", trapthread.ThreadID())\n\t\t\t}\n\t\t} else {\n\t\t\ttraptgt = grp.targets[0]\n\t\t}\n\t\ttraptgt.StopReason = stopReason\n\n\t\tit := ValidTargets{Group: grp}\n\t\tfor it.Next() {\n\t\t\t// Both selectedGoroutine and current thread are stale here, since we can\n\t\t\t// only set their definitive value *after* evaluating breakpoint\n\t\t\t// conditions here we give them temporary non-stale values.\n\t\t\tit.selectedGoroutine = nil\n\t\t\tcurthread := it.currentThread\n\t\t\tfor _, thread := range it.ThreadList() {\n\t\t\t\tif thread.Breakpoint().Breakpoint != nil {\n\t\t\t\t\tit.currentThread = thread\n\t\t\t\t\tthread.Breakpoint().Breakpoint.checkCondition(it.Target, thread, thread.Breakpoint())\n\t\t\t\t}","sourceCodeStart":82,"sourceCodeEnd":118,"githubUrl":"https://github.com/go-delve/delve/blob/a23773e6c31361e43246bc43a424ee009679b174/pkg/proc/target_exec.go#L82-L118","documentation":"During Continue, after the underlying process group stops on a trap thread, Delve maps the OS thread ID back to the debugged Target (process) it belongs to. If no target in the TargetGroup owns that thread, Continue returns this error because the debugger cannot attribute the stop event to any process.","triggerScenarios":"grp.Continue() (via ContinueOnce) returns a trapthread whose ThreadID is not present in any of grp.targets — e.g. a newly spawned/forked child process not yet registered, or a thread belonging to an exited/detached target.","commonSituations":"Multi-process debugging (follow-exec/follow-fork) where a child process appears before Delve registers it; attaching/detaching races during TestAttachDetach-style workflows; kernel/ptrace reporting a stop from a thread of a process Delve already removed.","solutions":["Update Delve — recent versions register fork/exec children with the TargetGroup before continuing, closing this race","Avoid combining follow-exec/follow-fork with rapid attach/detach of child processes in the same session","Check for the target process exiting concurrently (check /proc or process exit) so the thread no longer belongs to any known target","If reproducible, capture 'dlv --log' output and file an issue with the process/thread list at the time of the error"],"exampleFix":null,"handlingStrategy":"retry","validationCode":null,"typeGuard":null,"tryCatchPattern":"state, err := client.Continue()\nif err != nil && strings.Contains(err.Error(), \"could not find target for thread\") {\n    // transient multiprocess race: re-fetch state or retry once\n    state, err = client.GetState()\n    if err != nil {\n        return fmt.Errorf(\"continue failed: %w\", err)\n    }\n}","preventionTips":["Keep Delve updated for follow-exec/fork registration fixes","Avoid detaching child processes while continuing the parent in follow-fork sessions","Use 'dlv --log' to capture thread/target state when the error reproduces","Prefer current Go/Delve versions for multiprocess debugging"],"tags":["continue","thread","multiprocess"],"backgroundTag":"orphan-thread-no-target","analyzedSha":"a23773e6c31361e43246bc43a424ee009679b174","analyzedAt":"2026-08-31T15:12:45.221Z","schemaVersion":2},"datasetVersion":"2026-08-31T19:17:28.585Z"}