Segmentation fault while accessing a function-static structure via returned pointer

Question

I have the following structure:

struct sys_config_s
{
  char server_addr[256];
  char listen_port[100];
  char server_port[100];
  char logfile[PATH_MAX];
  char pidfile[PATH_MAX];
  char libfile[PATH_MAX];
  int  debug_flag;
  unsigned long connect_delay;
};
typedef struct sys_config_s sys_config_t;

I also have a function defined in a static library (let's call it A.lib):

sys_config_t* sys_get_config(void)
{
  static sys_config_t config;
  return &config;
}

I then have a program (let's call it B) and a dynamic library (let's call it C). Both B and C link with A.lib. At runtime B opens C via dlopen() and then gets an address to C's function func() via a call to dlsym().

void func(void)
{
  sys_get_config()->connect_delay = 1000;
}

The above code is the body of C's func() function and it produces a segmentation fault when reached. The segfault only occurs while running outside of gdb.

Why does that happen?

EDIT: Making sys_config_t config a global variable doesn't help.

Answer 1

The solution is trivial. Somehow, by a header mismatch, the PATH_MAX constant was defined differently in B's and C's compilation units. I need to be more careful in the future. (facepalms)