bar.c

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

#define MONO_NEVER_INLINE __attribute__ ((__noinline__))
#define MONO_API __attribute__((visibility("default")))

MONO_API void call2 (int* x);

static int count;

MONO_API
void call1 (int* x) {
	if (++count == 3) {
		void* foo[10];
		int n = backtrace (&foo[0], 10);
		if (n > 0) {
			char **syms = backtrace_symbols (&foo[0], n);
			for (int i = 0; i < n; ++i) {
				printf ("sym[%d] = %s\n", i, syms[i]);
			}
			free (syms);
		} else {
			printf ("no symbols");
		}
		return;
	} else
		call2 ((int*)&x);
}

compile.sh

clang -o foo -O3 -Wall -Wextra -fvisibility=hidden -g foo.c bar.c

foo.c

#include <stdio.h>

#define MONO_NEVER_INLINE __attribute__ ((noinline))
#define MONO_API __attribute__((visibility("default")))

MONO_API void call1 (int* x);


static
MONO_NEVER_INLINE
void 
static_fn (int *x)
{
	call1 ((int*)&x);
}

static int count;

// MONO_NEVER_INLINE
MONO_API
void call2 (int* x)
{
	if (++count > 3)
		return;
	if (++count == 0) {
		printf ("a\n");
		call2 (x);
		printf ("b\n");
	} else {
		static_fn (x);
		static_fn (x);
	}
}



int main (void)
{
	int x = 0;
	call1 (&x);
	return 0;
}

output.txt

static_fn with noinline attribute

./foo
sym[0] = 0   foo                                 0x000000010db14e65 call1 + 69
sym[1] = 1   foo                                 0x000000010db14df5 static_fn + 21
sym[2] = 2   foo                                 0x000000010db14da7 call2 + 55
sym[3] = 3   foo                                 0x000000010db14ece call1 + 174
sym[4] = 4   foo                                 0x000000010db14df5 static_fn + 21
sym[5] = 5   foo                                 0x000000010db14da7 call2 + 55
sym[6] = 6   foo                                 0x000000010db14ece call1 + 174
sym[7] = 7   foo                                 0x000000010db14e18 main + 24
sym[8] = 8   libdyld.dylib                       0x00007fff689317fd start + 1
sym[9] = 9   ???                                 0x0000000000000001 0x0 + 1

static_fn without noinline attribute
./foo
sym[0] = 0   foo                                 0x000000010eec9e65 call1 + 69
sym[1] = 1   foo                                 0x000000010eec9dc5 call2 + 53
sym[2] = 2   foo                                 0x000000010eec9ece call1 + 174
sym[3] = 3   foo                                 0x000000010eec9dc5 call2 + 53
sym[4] = 4   foo                                 0x000000010eec9ece call1 + 174
sym[5] = 5   foo                                 0x000000010eec9e18 main + 24
sym[6] = 6   libdyld.dylib                       0x00007fff689317fd start + 1
sym[7] = 7   ???                                 0x0000000000000001 0x0 + 1