使用backtrace和backtrace_symbols打印函数调用链

代码来源：http://man7.org/linux/man-pages/man3/backtrace.3.html

#include <execinfo.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

void myfunc3(void)
{
int j, nptrs;
#define SIZE 100
void *buffer[100];
char **strings;

nptrs = backtrace(buffer, SIZE);
printf("backtrace() returned %d addresses\n", nptrs);

/* The call backtrace_symbols_fd(buffer, nptrs, STDOUT_FILENO)
*               would produce similar output to the following: */

strings = backtrace_symbols(buffer, nptrs);
if (strings == NULL) {
perror("backtrace_symbols");
exit(EXIT_FAILURE);
}

for (j = 0; j < nptrs; j++)
printf("%s\n", strings[j]);

free(strings);
}

static void /* "static" means don't export the symbol... */ myfunc2(void)
{
myfunc3();
}

void myfunc(int ncalls)
{
if (ncalls > 1)
myfunc(ncalls - 1);
else
myfunc2();
}

int main(int argc, char *argv[])
{
if (argc != 2) {
fprintf(stderr, "%s num-calls\n", argv[0]);
exit(EXIT_FAILURE);
}

myfunc(atoi(argv[1]));
exit(EXIT_SUCCESS);
}

编译需要带上-rdynamic选项

$ cc -rdynamic prog.c -o prog

运行结果

$ ./prog 3
backtrace() returned 8 addresses
./prog(myfunc3+0x5c) [0x80487f0]
./prog [0x8048871]
./prog(myfunc+0x21) [0x8048894]
./prog(myfunc+0x1a) [0x804888d]
./prog(myfunc+0x1a) [0x804888d]
./prog(main+0x65) [0x80488fb]
/lib/libc.so.6(__libc_start_main+0xdc) [0xb7e38f9c]
./prog [0x8048711]

注意函数myfunc2使用了static

在编译时候被优化掉了

打印的调用链里没有myfunc2函数