sigemptyset（）正在覆盖下一个变量

Question

I have global variables

int a[10];
struct sigaction act;
int b[10];

Whenever I call

sigemptyset(&act.sa_mask); 

array a is getting corrupted. I doubt if it is compiler issue. I am using CodeSourcery mips-linux-gnu-gcc version 4.5.2. I compile using

mips-linux-gnu-gcc -c -g -muclibc -pedantic -Wno-declaration-after-statement -std=gnu99 -G 0 -mips2 -msoft-float -mno-memcpy -fomit-frame-pointer -pipe -Wall -Wstrict-prototypes signal/signal.c

mips-linux-gnu-gcc -G 0 -msoft-float -static -o signal  signal.o

My complete code follows:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
int a[10];
struct sigaction act;
int b[10];


int main ();
int main ()
{
int i;
//initialize a and b
for(i = 0 ; i < 10;i++)
{
    a[i]=1;b[i]=1;
}

sigemptyset(&act.sa_mask);

//print
for(i = 0 ; i < 10;i++)
{
    printf("%d %d ",a[i],b[i]);
}

return 0;
}

I found that using the -muclibc option for compiling causes this issue.

Answer 1

You are showing the struct sigaction act after the a array, but in the code you mention a siginfo variable, not act .

Could siginfo be declared before the a array ? Could you show what that function is doing ?

Answer 2

i found the answer I am not linking with -muclibc option

mips-linux-gnu-gcc -G 0 -msoft-float -static -muclibc -o signal  signal.o

will solve the problem

so while compiling it is is using sigset.h from uclibc and while executing it was executing code from libc( signal.c sigemptyset() )

and if you digdown further _SIGSET_NWORDS for mips is 4 while for x86 it is 32 so sigemptyset() was running for 32 iteration instead of 4