golang gdb - 打印变量

Question

我有 gdb 无法正确打印变量的问题。简单的程序是通过以下方式构建的：

chmurson-osx:helloworld chmurson$ go build -gcflags '-N' start.go 

然后 gdb 执行：

chmurson-osx:helloworld chmurson$ gdb start -d $GOROOT

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Reading symbols from start...done.

warning: Missing auto-load scripts referenced in section .debug_gdb_scripts

of file /Users/chmurson/Dev/goprojects/misc/src/helloworld/start

Use `info auto-load python-scripts [REGEXP]' to list them.

(gdb) 

(gdb) source /usr/local/go/src/pkg/runtime/runtime-gdb.py

Loading Go Runtime support.

这是我接下来要做的：

(gdb) list

1   package main

2   

3   import "fmt"

4   

5   func main() {

6       x := "abc"

7       i := 3

8       fmt.Println(i)

9       fmt.Println(x)

10  }

(gdb) b 9

Breakpoint 1 at 0x2106: file /Users/chmurson/Dev/goprojects/misc/src/helloworld/start.go, line 9.

(gdb) run

Starting program: /Users/chmurson/Dev/goprojects/misc/src/helloworld/start 

3

[New Thread 0x1113 of process 14039]

Breakpoint 1, main.main () at /Users/chmurson/Dev/goprojects/misc/src/helloworld/start.go:9

9       fmt.Println(x)

(gdb) p x

Python Exception <type 'exceptions.OverflowError'> signed integer is greater than maximum: 

$1 = 

(gdb) p i

$2 = 8725692800

(gdb) 

您可以看到在检查 'p' 变量时存在 Python 异常，而在显示 'i' 的值时完全不是 3。怎么了 ？

Answer 1

添加到@AlexAtNet 的答案中，Go 1.2.x 之后的所有内容都破坏了 GDB 支持，因此要么使用 go 1.2.x 进行调试，要么使用 gccgo（请记住，gcc 4.8.x 支持 go 1.1，gcc 4.9.x 最高为 1.2） .另一种选择是使用您自己的跟踪功能，虽然不漂亮，但它是目前 go 1.3+ 唯一真正的调试选项。我个人使用这样的东西进行调试：var traceLock sync.Mutexfunc trace(a ...interface{}) {&nbsp; &nbsp; traceLock.Lock()&nbsp; &nbsp; pc, f, ln, ok := runtime.Caller(1)&nbsp; &nbsp; fn := ""&nbsp; &nbsp; if ok {&nbsp; &nbsp; &nbsp; &nbsp; fn = runtime.FuncForPC(pc).Name()&nbsp; &nbsp; }&nbsp; &nbsp; fmt.Printf("trace: %s %s:%d", fn, filepath.Base(f), ln)&nbsp; &nbsp; if len(a) > 0 {&nbsp; &nbsp; &nbsp; &nbsp; fmt.Println(append([]interface{}{": "}, a...)...)&nbsp; &nbsp; }&nbsp; &nbsp; traceLock.Unlock()}