*** empty log message ***

[deliverable/binutils-gdb.git] / gdb / frame.c

diff --git a/gdb/frame.c b/gdb/frame.c
index 9ca69bf65966caed3a4ff6330d1f8756851b2b68..7932b48ee3b7a311dababb7b2b36ce446851df0a 100644 (file)
--- a/gdb/frame.c
+++ b/gdb/frame.c
@@ -324,7 +324,10 @@ get_frame_id (struct frame_info *fi)
       if (fi->unwind == NULL)
        fi->unwind = frame_unwind_find_by_frame (fi, &fi->prologue_cache);
       /* Find THIS frame's ID.  */
+      /* Default to outermost if no ID is found.  */
+      fi->this_id.value = outer_frame_id;
       fi->unwind->this_id (fi, &fi->prologue_cache, &fi->this_id.value);
+      gdb_assert (frame_id_p (fi->this_id.value));
       fi->this_id.p = 1;
       if (frame_debug)
        {
@@ -364,6 +367,7 @@ frame_unwind_caller_id (struct frame_info *next_frame)
 }
 
 const struct frame_id null_frame_id; /* All zeros.  */
+const struct frame_id outer_frame_id = { 0, 0, 0, 0, 0, 1, 0 };
 
 struct frame_id
 frame_id_build_special (CORE_ADDR stack_addr, CORE_ADDR code_addr,
@@ -405,6 +409,9 @@ frame_id_p (struct frame_id l)
   int p;
   /* The frame is valid iff it has a valid stack address.  */
   p = l.stack_addr_p;
+  /* outer_frame_id is also valid.  */
+  if (!p && memcmp (&l, &outer_frame_id, sizeof (l)) == 0)
+    p = 1;
   if (frame_debug)
     {
       fprintf_unfiltered (gdb_stdlog, "{ frame_id_p (l=");
@@ -427,7 +434,14 @@ int
 frame_id_eq (struct frame_id l, struct frame_id r)
 {
   int eq;
-  if (!l.stack_addr_p || !r.stack_addr_p)
+  if (!l.stack_addr_p && l.special_addr_p && !r.stack_addr_p && r.special_addr_p)
+    /* The outermost frame marker is equal to itself.  This is the
+       dodgy thing about outer_frame_id, since between execution steps
+       we might step into another function - from which we can't
+       unwind either.  More thought required to get rid of
+       outer_frame_id.  */
+    eq = 1;
+  else if (!l.stack_addr_p || !r.stack_addr_p)
     /* Like a NaN, if either ID is invalid, the result is false.
        Note that a frame ID is invalid iff it is the null frame ID.  */
     eq = 0;
@@ -1425,7 +1439,7 @@ get_prev_frame_1 (struct frame_info *this_frame)
      unwind to the prev frame.  Be careful to not apply this test to
      the sentinel frame.  */
   this_id = get_frame_id (this_frame);
-  if (this_frame->level >= 0 && !frame_id_p (this_id))
+  if (this_frame->level >= 0 && frame_id_eq (this_id, outer_frame_id))
     {
       if (frame_debug)
        {