我正在尝试为两个不同的Linux环境构建一个简单的C程序。在一台设备上,程序可以正常运行;而在另一台设备上,程序会生成浮点异常。该程序仅从主函数返回0,这使我相信可能存在一些与启动代码(可能是ABI)不兼容的问题。
使用gcc编译程序时,采用了以下构建规格:
使用内置规格。目标:i386-redhat-linux。配置为: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-libgcj-multifile --enable-languages=c,c++,objc,obj-c++,java,fortran,ada --enable-java-awt=gtk --disable-dssi --disable-plugin --with-java-home=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0/jre --with-cpu=generic --host=i386-redhat-linux 线程模型:posix,gcc版本4.1.2 20080704 (Red Hat 4.1.2-52)
该程序的源代码如下:
int main()
{
return(0);
}
在 Celeron 设备上,在 GDB 下执行此程序会生成以下输出:
[root@n00200C30AA2F jrn]# /jrn/gdb fail GNU gdb Red Hat Linux (5.3post-0.20021129.18rh) (gdb) run Starting program: /jrn/fail
Program received signal SIGFPE, Arithmetic exception. 0x40001cce in ?? () (gdb) bt
#0 0x40001cce in ?? ()
#1 0x4000c6b0 in ?? ()
#2 0x40000cb5 in ?? ()
以下是我能想到的细节,可以帮助找出发生了什么:
CELERON: ( fails on this device )
2.6.8 #21 Mon Oct 1 11:41:47 PDT 2007 i686 i686 i386 GNU/Linux
============
[root@n00200C30AA2F proc]# cat cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 9
model name : Intel(R) Celeron(R) M processor 600MHz
stepping : 5
cpu MHz : 599.925
cache size : 512 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr mce cx8 sep mtrr pge mca cmov pat clflush dts acpi mmx fxsr sse sse2 tm pbe
bogomips : 1179.64
GNU C Library stable release version 2.3.2, by Roland McGrath et al.
Compiled by GNU CC version 3.2.2 20030222 (Red Hat Linux 3.2.2-5).
Compiled on a Linux 2.4.20 system on 2003-03-13.
Available extensions:
GNU libio by Per Bothner
crypt add-on version 2.1 by Michael Glad and others
linuxthreads-0.10 by Xavier Leroy
BIND-8.2.3-T5B
libthread_db work sponsored by Alpha Processor Inc
NIS(YP)/NIS+ NSS modules 0.19 by Thorsten Kukuk
ATOM: ( works fine on this device )
2.6.35 #25 SMP Mon Mar 12 09:02:45 PDT 2012 i686 i686 i386 GNU/Linux
==========
[root@n00E04B36ECE5 ~]# cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 28
model name : Genuine Intel(R) CPU N270 @ 1.60GHz
stepping : 2
cpu MHz : 1599.874
cache size : 512 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 10
wp : yes
flags : fpu vme de tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx constant_tsc up arch_perfmon pebs bts aperfmperf pni dtes64 monitor ds_cpl est tm2 ssse3 xtpr pdcm movbe lahf_lm
bogomips : 3199.74
clflush size : 64
cache_alignment : 64
address sizes : 32 bits physical, 32 bits virtual
power management:
GNU C Library stable release version 2.5, by Roland McGrath et al.
Compiled by GNU CC version 4.1.2 20080704 (Red Hat 4.1.2-44).
Compiled on a Linux 2.6.9 system on 2009-09-02.
Available extensions:
The C stubs add-on version 2.1.2.
crypt add-on version 2.1 by Michael Glad and others
GNU Libidn by Simon Josefsson
GNU libio by Per Bothner
NIS(YP)/NIS+ NSS modules 0.19 by Thorsten Kukuk
Native POSIX Threads Library by Ulrich Drepper et al
BIND-8.2.3-T5B
RT using linux kernel aio
Thread-local storage support included.
我该怎么确定是什么导致了这个问题?
不妨尝试使用特定版本的libc进行静态链接,看是否能够解决问题。
当出现错误时,在GDB下执行以下命令:
(gdb) x/1i $eip 0x40001cce: divl 0x164(%ecx)
(gdb) info reg
eax 0x6c994f 7117135
ecx 0x40012858 1073817688
edx 0x0 0
ebx 0x40012680 1073817216
esp 0xbffff740 0xbffff740
ebp 0xbffff898 0xbffff898
esi 0x8049580 134518144
edi 0x400125cc 1073817036
eip 0x40001cce 0x40001cce
eflags 0x10246 66118
cs 0x73 115
ss 0x7b 123
ds 0x7b 123
es 0x7b 123
fs 0x0 0
gs 0x0 0
(gdb) x/1wx 0x164+$ecx
0x400129bc: 0x00000000
(gdb)
根据我得到的帮助,似乎是由于libc启动代码除以0的原因。
现在的问题是,是什么导致了这种明显的错误行为?某些东西一定与其他某些东西不兼容?
汇编输出:
[jrn@localhost ~]$ more fail.s
.file "fail.c"
.text
.globl main
.type main, @function
main:
leal 4(%esp), %ecx
andl $-16, %esp
pushl -4(%ecx)
pushl %ebp
movl %esp, %ebp
pushl %ecx
movl $0, %eax
popl %ecx
popl %ebp
leal -4(%ecx), %esp
ret
.size main, .-main
.ident "GCC: (GNU) 4.1.2 20080704 (Red Hat 4.1.2-52)"
.section .note.GNU-stack,"",@progbits
x/1i $eip
吗? - ninjalj