#include <stdlib.h>
#include <dlfcn.h>
#include <pthread.h>
+#ifdef HAVE_EXECINFO_H
+# include <execinfo.h>
+#endif
static void vlogbug (const char *level, const char *func, const char *fmt,
va_list ap)
{
+#ifdef HAVE_BACKTRACE
+ const size_t framec = 8;
+ void *framev[framec];
+
+ backtrace (framev, framec);
+#endif
flockfile (stderr);
fprintf (stderr, "%s: call to %s(", level, func);
vfprintf (stderr, fmt, ap);
fputs (")\n", stderr);
+ fflush (stderr);
+#ifdef HAVE_BACKTRACE
+ backtrace_symbols_fd (framev + 2, framec - 2, fileno (stderr));
+#endif
funlockfile (stderr);
}