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[PATCH] Catch errors in value_get_print_value
- From: Nick Roberts <nickrob at snap dot net dot nz>
- To: gdb-patches at sourceware dot org
- Date: Fri, 2 Feb 2007 09:51:39 +1300
- Subject: [PATCH] Catch errors in value_get_print_value
Currently when common_val_print throws an error from install_new_value it gets
caught in mi_execute_command and prints an MI error (^error,...) without
cleaning up. This patch catches the error in value_get_print_value so that GDB
can proceed normally. It could be adapted to output something like
"<error_reading_variable>" but I think the empty string works better.
To see what currently happens, compile:
#include <stdlib.h>
typedef struct {
float a;
float b;
} substruct;
struct substruct1 {
float a1;
substruct b1;
};
main () {
struct substruct1 *abc4 = NULL;
int i = 1;
}
-------------------
and run under GDB as follows:
~"Using host libthread_db library \"/lib/libthread_db.so.1\".\n"
(gdb)
start
&"start\n"
Breakpoint 1 at 0x8048365: file temp4.c, line 15.
Starting program: /home/nickrob/temp4
main () at temp4.c:15
15 struct substruct1 *abc4 = NULL;
^done
(gdb)
n
&"n\n"
16 int i = 1;
^done
(gdb)
-var-create - * abc4
^done,name="var1",numchild="2",type="struct substruct1 *"
(gdb)
-var-list-children --all-values var1
&"Cannot access memory at address 0x4\n"
^error,msg="Cannot access memory at address 0x4"
(gdb)
-var-list-children --all-values var1
&&"Duplicate variable object name\n"
^error,msg="Duplicate variable object name"
(gdb)
--
Nick http://www.inet.net.nz/~nickrob
2007-02-02 Nick Roberts <nickrob@snap.net.nz>
* varobj.c (value_get_print_value): Catch errors from
common_val_print.
*** varobj.c 02 Feb 2007 09:32:33 +1300 1.82
--- varobj.c 02 Feb 2007 09:48:59 +1300
*************** value_get_print_value (struct value *val
*** 1702,1707 ****
--- 1702,1708 ----
struct ui_file *stb;
struct cleanup *old_chain;
char *thevalue;
+ struct gdb_exception except;
if (value == NULL)
return NULL;
*************** value_get_print_value (struct value *val
*** 1709,1715 ****
stb = mem_fileopen ();
old_chain = make_cleanup_ui_file_delete (stb);
! common_val_print (value, stb, format_code[(int) format], 1, 0, 0);
thevalue = ui_file_xstrdup (stb, &dummy);
do_cleanups (old_chain);
--- 1710,1720 ----
stb = mem_fileopen ();
old_chain = make_cleanup_ui_file_delete (stb);
! TRY_CATCH (except, RETURN_MASK_ERROR)
! {
! common_val_print (value, stb, format_code[(int) format], 1, 0, 0);
! }
!
thevalue = ui_file_xstrdup (stb, &dummy);
do_cleanups (old_chain);