[binutils-gdb] stack: check frame_unwind_caller_id

[Markus Metzger <mmetzger at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=a038fa3e14a477d4d72a26c2e139fa47d2774be2

commit a038fa3e14a477d4d72a26c2e139fa47d2774be2
Author: Markus Metzger <markus.t.metzger@intel.com>
Date:   Thu Feb 11 11:07:09 2016 +0100

    stack: check frame_unwind_caller_id
    
    Callers of frame_unwind_caller_* functions are supposed to check
    frame_unwind_caller_id.
    
    Add such a check to frame_info and treat an invalid caller ID as if the caller
    PC were not available.
    
    gdb/
    	* stack.c (frame_info): Check frame_unwind_caller_id.

Diff:
---
 gdb/ChangeLog |  4 ++++
 gdb/stack.c   | 39 ++++++++++++++++++++++-----------------
 2 files changed, 26 insertions(+), 17 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index d21bb3f..ef88180 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,9 @@
 2016-02-12  Markus Metzger  <markus.t.metzger@intel.com>
 
+	* stack.c (frame_info): Check frame_unwind_caller_id.
+
+2016-02-12  Markus Metzger  <markus.t.metzger@intel.com>
+
 	* frame.h (skip_tailcall_frames): New.
 	* frame.c (skip_tailcall_frames): New.
 	(frame_pop): Call skip_tailcall_frames.
diff --git a/gdb/stack.c b/gdb/stack.c
index 89879f3..6e3acc7 100644
--- a/gdb/stack.c
+++ b/gdb/stack.c
@@ -1509,27 +1509,32 @@ frame_info (char *addr_exp, int from_tty)
   wrap_here ("    ");
   printf_filtered ("saved %s = ", pc_regname);
 
-  TRY
-    {
-      caller_pc = frame_unwind_caller_pc (fi);
-      caller_pc_p = 1;
-    }
-  CATCH (ex, RETURN_MASK_ERROR)
+  if (!frame_id_p (frame_unwind_caller_id (fi)))
+    val_print_unavailable (gdb_stdout);
+  else
     {
-      switch (ex.error)
+      TRY
 	{
-	case NOT_AVAILABLE_ERROR:
-	  val_print_unavailable (gdb_stdout);
-	  break;
-	case OPTIMIZED_OUT_ERROR:
-	  val_print_not_saved (gdb_stdout);
-	  break;
-	default:
-	  fprintf_filtered (gdb_stdout, _("<error: %s>"), ex.message);
-	  break;
+	  caller_pc = frame_unwind_caller_pc (fi);
+	  caller_pc_p = 1;
 	}
+      CATCH (ex, RETURN_MASK_ERROR)
+	{
+	  switch (ex.error)
+	    {
+	    case NOT_AVAILABLE_ERROR:
+	      val_print_unavailable (gdb_stdout);
+	      break;
+	    case OPTIMIZED_OUT_ERROR:
+	      val_print_not_saved (gdb_stdout);
+	      break;
+	    default:
+	      fprintf_filtered (gdb_stdout, _("<error: %s>"), ex.message);
+	      break;
+	    }
+	}
+      END_CATCH
     }
-  END_CATCH
 
   if (caller_pc_p)
     fputs_filtered (paddress (gdbarch, caller_pc), gdb_stdout);