[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
bug#21438: 25.0.50; GUD locals frame/window doesn't shows struct values
From: |
Eli Zaretskii |
Subject: |
bug#21438: 25.0.50; GUD locals frame/window doesn't shows struct values as nil |
Date: |
Wed, 09 Sep 2015 17:14:24 +0300 |
> From: Tassilo Horn <tsdh@gnu.org>
> Date: Wed, 09 Sep 2015 08:04:49 +0200
>
> stepping till the end of the function, this is the contents of the
> locals buffer shows:
>
> --8<---------------cut here---------------start------------->8---
> struct it it nil
> struct text_pos pt nil
> struct window * w 0x12a1d40
> struct buffer * old_buffer 0x0
> Lisp_Object result 58
> --8<---------------cut here---------------end--------------->8---
>
> But it and pt cannot be NULL/nil (and they are not when checking with
> "info locals" in the GUD GDB buffer).
>
> The reason for that is that GUD uses the GDB command "-stack-list-locals
> --thread X --simple-values" as defined in gdb-mi.el:3991 which returns:
>
> locals=[{name="it",type="struct it"},
> {name="pt",type="struct text_pos"},
> {name="w",type="struct window *",value="0x12a1d40"},
> {name="old_buffer",type="struct buffer *",value="0x0"},
> {name="result",type="Lisp_Object",value="58"}]
>
> Note that the entries for the two structs it and pt don't have a value
> field.
>
> I guess the usage of --simple-values is intentional, and in fact, when
> trying to use "--all-values" instead I get a
>
> error in process filter: gdb-jsonify-buffer: Stack overflow in regexp
> matcher
Yes, the use of --simple-values is intentional. If you want to see
the values of the fields, you need to click mouse-2 on the variable
name, and then Emacs will pop up a frame with the fields.
> I'm not actually sure if it would be benefitical to use --all-values
> even if that regexp matching error was fixed because the structs can be
> really large. But at least the value should not be shown as "nil" but
> as "<non-simple value>" or something else which makes it obvious that
> the displayed value is not the real value.
Like the patch below? If you think it's OK, I will push it.
Thanks.
--- lisp/progmodes/gdb-mi.el~0 2015-05-20 08:22:42.000000000 +0300
+++ lisp/progmodes/gdb-mi.el 2015-09-09 16:47:24.399310500 +0300
@@ -4038,6 +4038,8 @@
(let ((name (bindat-get-field local 'name))
(value (bindat-get-field local 'value))
(type (bindat-get-field local 'type)))
+ (when (not value)
+ (setq value "<complex data type>"))
(if (or (not value)
(string-match "\\0x" value))
(add-text-properties 0 (length name)