Re: [PATCH v2 5/5] GDB: Introduce limited array lengths while printing values

[Eli Zaretskii <eliz@gnu.org>]

> Date: Thu, 12 Jan 2023 09:02:23 +0000 (GMT)
> From: "Maciej W. Rozycki" <macro@embecosm.com>
> cc: Andrew Burgess <aburgess@redhat.com>, Tom Tromey <tom@tromey.com>, 
>  Richard Bunt <Richard.Bunt@arm.com>
> 
> --- src.orig/gdb/NEWS
> +++ src/gdb/NEWS
> @@ -354,6 +354,12 @@ GDB now supports floating-point on Loong
>    Disabling this can cause a performance penalty when there are a lot of
>    symbols to load, but is useful for debugging purposes.
>  
> +* The 'set print elements' setting now helps when printing large arrays.
> +  If an array would otherwise exceed max-value-size, but 'print elements'
> +  is set such that the number of elements to print is less than or equal
> +  to 'max-value-size', GDB will now still print the array, however only
> +  'max-value-size' worth of data will be added into the value history.

The wording here needs to be changed, because max-value-size is not
about the number of elements, it's about the amount of memory needed
for those elements.  So this part:

                                                       but 'print elements'
     is set such that the number of elements to print is less than or equal
     to 'max-value-size'

should be reworded.

> --- src.orig/gdb/doc/gdb.texinfo
> +++ src/gdb/doc/gdb.texinfo
> @@ -11756,6 +11756,14 @@ When @value{GDBN} starts, this limit is
>  Setting @var{number-of-elements} to @code{unlimited} or zero means
>  that the number of elements to print is unlimited.
>  
> +When printing very large arrays, whose size is greater than
> +@code{max-value-size} (@pxref{set max-value-size,,max-value-size}),
> +if the @code{print elements} is set such that the size of the elements
> +being printed is less than or equal to @code{max-value-size}, then
> +@value{GDBN} will print the array (up to the @code{print elements} limit),
> +and only @code{max-value-size} worth of data will be added into the value
> +history (@pxref{Value History, ,Value History}).
> +
>  @item show print elements
>  Display the number of elements of a large array that @value{GDBN} will print.
>  
> @@ -14171,6 +14179,7 @@ may indicate a value that is incorrectly
>  @value{GDBN} to try and allocate an overly large amount of memory.
>  
>  @table @code
> +@anchor{set max-value-size}
>  @kindex set max-value-size
>  @item set max-value-size @var{bytes}
>  @itemx set max-value-size unlimited

This part is OK.

Thanks.