我遇到了gdb不能正确打印变量的问题。这个简单的程序是这样构建的:
chmurson-osx:helloworld chmurson$ go build -gcflags '-N' start.go
然后gdb执行了:
chmurson-osx:helloworld chmurson$ gdb start -d $GOROOT
GNU gdb (GDB) 7.8
Copyright (C) 2014 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-apple-darwin14.0.0".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
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.
下一步我会这样做:
(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
$2 = 8725692800
(gdb)
你可以看到在检查'p'变量时出现了Python异常,并且在显示'i'的值时完全不是3。出了什么问题?
这是我的Go版本
chmurson-osx:helloworld chmurson$ go version
go version go1.3.1 darwin/amd64
以及 gdb 配置
(gdb) show configuration
This GDB was configured as follows:
configure --host=x86_64-apple-darwin14.0.0 --target=x86_64-apple-darwin14.0.0
--with-auto-load-dir=:${prefix}/share/auto-load
--with-auto-load-safe-path=:${prefix}/share/auto-load
--with-expat
--with-gdb-datadir=/usr/local/share/gdb (relocatable)
--with-jit-reader-dir=/usr/local/lib/gdb (relocatable)
--without-libunwind-ia64
--without-lzma
--with-python=/System/Library/Frameworks/Python.framework/Versions/2.7
--without-guile
--with-separate-debug-dir=/usr/local/lib/debug (relocatable)
--with-zlib
--without-babeltrace
("Relocatable" means the directory can be moved with the GDB installation
tree, and GDB will still find it.)