go runtime_error ai_generated true

invalid memory address or nil pointer dereference [signal SIGSEGV: segmentation violation]

ID: go/invalid-memory-address-or-nil-pointer-dereference-in-select

Also available as: JSON · Markdown · 中文
90%Fix Rate
86%Confidence
1Evidence
2023-08-05First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
go1.18 active — — —
go1.19 active — — —
go1.20 active — — —
go1.21 active — — —

Root Cause

Dereferencing a nil pointer in a goroutine, often inside a select statement or channel operation where a pointer was not properly initialized.

generic

中文

在 goroutine 中解引用空指针，通常发生在 select 语句或通道操作中，指针未正确初始化。

Official Documentation

https://go.dev/doc/faq#nil_error

Workarounds

  1. 95% success Add explicit nil checks before dereferencing: `if ptr != nil { ptr.Field = value } else { log.Fatal("ptr is nil") }` 
    Add explicit nil checks before dereferencing: `if ptr != nil { ptr.Field = value } else { log.Fatal("ptr is nil") }`
  2. 90% success Initialize all pointers with make or new before use: `ptr = new(StructType)` or `ptr = &StructType{}` 
    Initialize all pointers with make or new before use: `ptr = new(StructType)` or `ptr = &StructType{}`

中文步骤

  1. Add explicit nil checks before dereferencing: `if ptr != nil { ptr.Field = value } else { log.Fatal("ptr is nil") }`
  2. Initialize all pointers with make or new before use: `ptr = new(StructType)` or `ptr = &StructType{}`

Dead Ends

Common approaches that don't work:

  1. 90% fail

    SIGSEGV is a signal, not a panic; recover() cannot catch segmentation violations—the program still crashes.

  2. 70% fail

    Nil pointer dereference is not a race condition; the pointer is nil regardless of synchronization.