gcc gdb调试 段错误 停在了 libc.so 如何查看函数栈中 参数值

GDB调试停在了glibc中，如何查看如何查看函数栈中，参数值？

bt命令：

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x920f6b70 (LWP 5472)]
0xb5045559 in ?? () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
(gdb) bt
#0  0xb5045559 in ?? () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
#1  0xb50484ac in ?? () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
#2  0xb50489dd in realloc () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
#3  0xb7f310ad in xrRealloc (ptr=0xa8d8f90, size=26896) at ../../base/mem/mem_cmn.c:53
#4  0xb4b84fd2 in initRGAnaVal (pMsg=0xa8d8d80, sum=1681) at ../../../frcore/rarecorder/src/reccomtrade.c:1757
#5  0xb4b87cd2 in getCTriggerMsg () at ../../../frcore/rarecorder/src/reccomtrade.c:2609
#6  0xb4b88fb1 in getTrigger () at ../../../frcore/rarecorder/src/reccomtrade.c:3033
#7  0xb4b89036 in processData () at ../../../frcore/rarecorder/src/reccomtrade.c:3069
#8  0xb4b883d7 in processComtrade () at ../../../frcore/rarecorder/src/reccomtrade.c:2792
#9  0xb4ba95cf in recProcessSV (pSV=0x8a845798) at ../../../frcore/rarecorder/src/recprocessor.c:468
#10 0xb4b78487 in recSvTask (arg=0x0) at ../../../frcore/rarecorder/src/frprot.c:162
#11 0xb7fc1c39 in start_thread () from /lib/i386-linux-gnu/i686/cmov/libpthread.so.0
#12 0xb50a8d2e in clone () from /lib/i386-linux-gnu/i686/cmov/libc.so.6

停在libc.so中了。list命令由于找不到库代码，直接停在了main入口。直接p命令打印函数栈中的参数，找不到。

那么，使用f命令，沿着调用栈找吧。

(gdb) f 4
#4  0xb4b84fd2 in initRGAnaVal (pMsg=0xa8d8d80, sum=1681) at ../../../frcore/rarecorder/src/reccomtrade.c:1757
1757                    if ((pVal = xrRealloc(pMsg->pVal, sum*xrSZOF(GANA_VAL))) == NULL)
(gdb) 

(gdb) p pVal
$1 = (GANA_VAL *) 0x0

参考：

http://blog.youkuaiyun.com/linfeng999/article/details/38413945