libunwind: undefined reference to `_Ux86_64_getcontext' when compiling on Debian bullseye

Question

When trying to compile the program

#include <stdio.h>
#include <stdlib.h>
#include <libunwind.h>

int main(int argc, char **argv)
{
    unw_cursor_t cursor;
    unw_context_t context;

    // grab the machine context and initialize the cursor
    if (unw_getcontext(&context) < 0)
        printf("ERROR: cannot get local machine state\n");
    
    if (unw_init_local(&cursor, &context) < 0)
        printf("ERROR: cannot initialize cursor for local unwinding\n");

    return 1;
}

with

gcc -lunwind main.c -o test

I do get following error:

/usr/bin/ld: /tmp/ccFDiWBz.o: in function `main':
main.c:(.text+0x23): undefined reference to `_Ux86_64_getcontext'
/usr/bin/ld: main.c:(.text+0x4c): undefined reference to `_Ux86_64_init_local'
collect2: error: ld returned 1 exit status

I have installed libunwind-dev and can see that the Symbols are in libunwind.so.8.0.1.

Do I have to link the library in a different way or what else could be the problem?

Answer 1

Putting

#define UNW_LOCAL_ONLY 

before

#include <libunwind.h>

solved the problem.