X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fc-stack.c;h=2f902af3a436c355c6d41fd72b9c73654cb5054f;hb=2726ca8984e8d2d8edf288b4d1d7007bfca0d82e;hp=bff346bd97f5329fe684bde3ec13e9fcba00910b;hpb=f607ad3bb9988f9a7bf0b6d3f18f92bdee12724c;p=gnulib.git

diff --git a/lib/c-stack.c b/lib/c-stack.c
index bff346bd9..2f902af3a 100644
--- a/lib/c-stack.c
+++ b/lib/c-stack.c
@@ -104,17 +104,16 @@ static char const * volatile stack_overflow_message;
    appears to have been a stack overflow, or with a core dump
    otherwise.  This function is async-signal-safe.  */
 
-static void die (int) __attribute__ ((noreturn));
-static void
+static _Noreturn void
 die (int signo)
 {
   char const *message;
-#if !SIGINFO_WORKS
+#if !SIGINFO_WORKS && !HAVE_LIBSIGSEGV
   /* We can't easily determine whether it is a stack overflow; so
      assume that the rest of our program is perfect (!) and that
      this segmentation violation is a stack overflow.  */
   signo = 0;
-#endif /* !SIGINFO_WORKS */
+#endif /* !SIGINFO_WORKS && !HAVE_LIBSIGSEGV */
   segv_action (signo);
   message = signo ? program_error_message : stack_overflow_message;
   ignore_value (write (STDERR_FILENO, program_name, strlen (program_name)));
@@ -182,9 +181,7 @@ static int segv_handler (void *address __attribute__ ((unused)),
 /* Handle a segmentation violation that is likely to be a stack
    overflow and exit.  This function is async-signal-safe.  */
 
-static void overflow_handler (int, stackoverflow_context_t)
-  __attribute__ ((noreturn));
-static void
+static _Noreturn void
 overflow_handler (int emergency,
                   stackoverflow_context_t context __attribute__ ((unused)))
 {
@@ -223,29 +220,12 @@ c_stack_action (void (*action) (int))
 
 #elif HAVE_SIGALTSTACK && HAVE_DECL_SIGALTSTACK && HAVE_STACK_OVERFLOW_HANDLING
 
-/* Direction of the C runtime stack.  This function is
-   async-signal-safe.  */
-
-# if STACK_DIRECTION
-#  define find_stack_direction(ptr) STACK_DIRECTION
-# else
-#  if ! SIGINFO_WORKS || HAVE_XSI_STACK_OVERFLOW_HEURISTIC
-static int
-find_stack_direction (char const *addr)
-{
-  char dummy;
-  return ! addr ? find_stack_direction (&dummy) : addr < &dummy ? 1 : -1;
-}
-#  endif
-# endif
-
 # if SIGINFO_WORKS
 
 /* Handle a segmentation violation and exit.  This function is
    async-signal-safe.  */
 
-static void segv_handler (int, siginfo_t *, void *) __attribute__((noreturn));
-static void
+static _Noreturn void
 segv_handler (int signo, siginfo_t *info,
               void *context __attribute__ ((unused)))
 {
@@ -266,17 +246,14 @@ segv_handler (int signo, siginfo_t *info,
   if (0 < info->si_code)
     {
       /* If the faulting address is within the stack, or within one
-         page of the stack end, assume that it is a stack
-         overflow.  */
+         page of the stack, assume that it is a stack overflow.  */
       ucontext_t const *user_context = context;
       char const *stack_base = user_context->uc_stack.ss_sp;
       size_t stack_size = user_context->uc_stack.ss_size;
       char const *faulting_address = info->si_addr;
-      size_t s = faulting_address - stack_base;
       size_t page_size = sysconf (_SC_PAGESIZE);
-      if (find_stack_direction (NULL) < 0)
-        s += page_size;
-      if (s < stack_size + page_size)
+      size_t s = faulting_address - stack_base + page_size;
+      if (s < stack_size + 2 * page_size)
         signo = 0;
 
 #   if DEBUG