Index: buildsym.h
===================================================================
RCS file: /cvs/src/src/gdb/buildsym.h,v
retrieving revision 1.6
diff -u -r1.6 buildsym.h
--- buildsym.h	8 Nov 2002 20:05:10 -0000	1.6
+++ buildsym.h	15 Nov 2002 20:47:34 -0000
@@ -22,6 +22,8 @@
 #if !defined (BUILDSYM_H)
 #define BUILDSYM_H 1
 
+#include "gdb_assert.h"
+
 /* This module provides definitions used for creating and adding to
    the symbol table.  These routines are called from various symbol-
    file-reading routines.
@@ -173,12 +175,6 @@
 
 EXTERN int context_stack_size;
 
-/* Macro "function" for popping contexts from the stack.  Pushing is
-   done by a real function, push_context.  This returns a pointer to a
-   struct context_stack.  */
-
-#define	pop_context() (&context_stack[--context_stack_depth]);
-
 /* Non-zero if the context stack is empty.  */
 #define outermost_context_p() (context_stack_depth == 0)
 
@@ -271,6 +267,13 @@
 extern void buildsym_init (void);
 
 extern struct context_stack *push_context (int desc, CORE_ADDR valu);
+
+/* Macro "function" for popping contexts from the stack.  Pushing is
+   done by a real function, push_context.  This returns a pointer to a
+   struct context_stack.  */
+
+#define pop_context() \
+  (gdb_assert (context_stack_depth > 0), &context_stack[--context_stack_depth]);
 
 extern void record_line (struct subfile *subfile, int line, CORE_ADDR pc);
 
Index: dbxread.c
===================================================================
RCS file: /cvs/src/src/gdb/dbxread.c,v
retrieving revision 1.36
diff -u -r1.36 dbxread.c
--- dbxread.c	25 Oct 2002 22:25:55 -0000	1.36
+++ dbxread.c	15 Nov 2002 20:47:42 -0000
@@ -2774,6 +2774,13 @@
 	{
 	  /* This N_FUN marks the end of a function.  This closes off the
 	     current block.  */
+
+ 	  if (context_stack_depth <= 0)
+ 	    {
+ 	      complain (&lbrac_mismatch_complaint, symnum);
+ 	      break;
+ 	    }
+
 	  record_line (current_subfile, 0, function_start_offset + valu);
 	  within_function = 0;
 	  new = pop_context ();
@@ -2842,6 +2849,12 @@
 	/* On most machines, the block addresses are relative to the
 	   N_SO, the linker did not relocate them (sigh).  */
 	valu += last_source_start_addr;
+
+      if (context_stack_depth <= 0)
+	{
+	  complain (&lbrac_mismatch_complaint, symnum);
+	  break;
+	}
 
       new = pop_context ();
       if (desc != new->depth)