Re: [RFA] Handle stack underflow in dbxread.c

[Jim Blandy <jimb@redhat.com>]

The context in your first patch hunk doesn't appear anywhere in my
sources.  Is this diff against the current sources?

Klee Dienes <klee@apple.com> writes:

> 2002-11-15  Klee Dienes  <kdienes@apple.com>
> 
>          * buildsym.h (pop_context): Check for stack underflow.
>          * dbxread.c (process_one_symbol): Complain and stop processing
>          that symbol if we are already at the top of the context stack
> for
>          a function-end N_FUN (this would imply an umatched RBRAC).
> Ditto
>          when processing N_RBRAC.
> 
> 
> 2002-11-15  Klee Dienes  <kdienes@apple.com>
>         
>         * buildsym.h (pop_context): Check for stack underflow.
>         * dbxread.c (process_one_symbol): Complain and stop processing
>         that symbol if we are already at the top of the context stack for
>         a function-end N_FUN (this would imply an umatched RBRAC).  Ditto
>         when processing N_RBRAC.
> 
> Index: dbxread.c
> ===================================================================
> RCS file: /cvs/Darwin/src/live/cygnus/src/gdb/dbxread.c,v
> retrieving revision 1.38
> diff -u -r1.38 dbxread.c
> --- dbxread.c	2002/10/26 09:20:14	1.38
> +++ dbxread.c	2002/11/15 08:56:07
> @@ -2946,6 +2946,11 @@
>  	      complain (&fun_end_outside_fun_complaint);
>  	      break;
>  	    }
> +	  if (context_stack_depth <= 0)
> +	    {
> +	      complain (&lbrac_mismatch_complaint, symnum);
> +	      break;
> +	    }
>  	  
>  	  saw_fun_start = 0;
>  	  record_line (current_subfile, 0, last_function_start + valu);
> @@ -3027,6 +3032,11 @@
>  	valu += last_source_start_addr;
>  #endif
>  
> +      if (context_stack_depth <= 0)
> +	{
> +	  complain (&lbrac_mismatch_complaint, symnum);
> +	  break;
> +	}
>        new = pop_context ();
>        if (desc != new->depth)
>  	complain (&lbrac_mismatch_complaint, symnum);
> Index: buildsym.h
> ===================================================================
> RCS file: /cvs/Darwin/src/live/cygnus/src/gdb/buildsym.h,v
> retrieving revision 1.5
> diff -u -r1.5 buildsym.h
> --- buildsym.h	2002/11/10 05:33:33	1.5
> +++ buildsym.h	2002/11/15 08:56:07
> @@ -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);
>