Re: breakpoints/1052: GDB 5.3 (macro supporting) - macro value is string without quotes.

[Daniel Jacobowitz <drow at mvista dot com>]

The following reply was made to PR breakpoints/1052; it has been noted by GNATS.

From: Daniel Jacobowitz <drow@mvista.com>
To: "Gvozdeva, Svetlana" <Svetlana_Gvozdeva@stl.sarov.ru>
Cc: gdb-gnats@sources.redhat.com, miwako.tokugawa@intel.com
Subject: Re: breakpoints/1052: GDB 5.3 (macro supporting) - macro value is string without quotes.
Date: Thu, 13 Feb 2003 11:03:10 -0500

 On Thu, Feb 13, 2003 at 08:47:58AM +0300, Gvozdeva, Svetlana wrote:
 > Hello, Daniel.
 > 
 > I think that it is not correct (I meant both 1052 && 1053).
 > If there is limit for printing of macro values then GDB's help should
 > contain information about it.
 > Right now I do  not see this information in help.
 > 
 > As I see GDB performs macro substitution in whole command line (that is why
 > we get bad command line).
 > But I think that command 'print' should print value for all kinds of macros.
 > 
 > First phase can be to find if command argument is exist (variable or macro
 > symbol) and second phase can be printing of macro value if argument is macro
 > symbol.
 > I think that printing of macro should be the similar to printing of
 > variable. If variable is visible then it should be variable value. If macro
 > is visible then it should be macro value.
 > 
 > As I see GDB prints 'p 234' without problem but symbol '234' is not variable
 > or macro symbol or other symbol.
 
 We don't special-case printing a variable; it's an expression
 evaluator.
 
 My point is that "p 234" prints the value of the C expression "234".  "p
 var" prints the value of the C expression "var".  "p MACRO" is printing
 the value of the C expression "MACRO" which happens to not be a valid
 expression.  I don't see a problem with the current behavior.
 
 Let's see if anyone else has an opinion.
 
 > -----Original Message-----
 > From: Daniel Jacobowitz [mailto:drow@mvista.com]
 > Sent: Wednesday, February 12, 2003 6:16 PM
 > To: Gvozdeva, Svetlana
 > Cc: gdb-gnats@sources.redhat.com; miwako.tokugawa@intel.com
 > Subject: Re: breakpoints/1052: GDB 5.3 (macro supporting) - macro value
 > is string without quotes.
 > 
 > 
 > On Wed, Feb 12, 2003 at 08:28:47AM -0000, sana@stl.sarov.ru wrote:
 > > 
 > > >Number:         1052
 > > >Category:       breakpoints
 > > >Synopsis:       GDB 5.3 (macro supporting) - macro value is string
 > without quotes.
 > > >Confidential:   no
 > > >Severity:       serious
 > > >Priority:       high
 > > >Responsible:    unassigned
 > > >State:          open
 > > >Class:          sw-bug
 > > >Submitter-Id:   net
 > > >Arrival-Date:   Wed Feb 12 08:38:00 UTC 2003
 > > >Closed-Date:
 > > >Last-Modified:
 > > >Originator:     sana@stl.sarov.ru
 > > >Release:        unknown-1.0
 > > >Organization:
 > > >Environment:
 > > 32-bit and 64-bit Linux, GDB 5.3
 > > >Description:
 > > GDB 5.3 supports work with section .debug_macinfo.
 > > During testing it has been found out that GDB 5.3 has problem with
 > printing of macro symbols whose value is string without quotes.
 > > But it is usual parctice to use such values.
 > > 
 > > tets.c:
 > > 
 > > #define PREFIX    small 
 > > main()
 > > {
 > > int PREFIX_i = 10, PREFIX_j;
 > > 
 > > PREFIX_j = abs(PREFIX_i);
 > > return;
 > > }
 > > 
 > > 
 > > GDB's output for this test is:
 > > 
 > > This GDB was configured as "i686-pc-linux-gnu"...
 > > (gdb) b main
 > > Breakpoint 1 at 0x8048aef: file test2.c, line 4.
 > > (gdb) r
 > > Starting program: /home1/sana/macro/tr/a.out 
 > > 
 > > Breakpoint 1, main () at test2.c:4
 > > 4       int PREFIX_i = 10, PREFIX_j;
 > > (gdb) p PREFIX
 > > No symbol "small" in current context.
 > > (gdb) 
 > 
 > Same question as for your other report - why do you think this is a
 > bug, and what do you expect GDB to do when you say "p PREFIX"?  "macro
 > expand PREFIX" will work, but "PREFIX" as an expression is a syntax
 > error because small is undeclared.
 > 
 > 
 > -- 
 > Daniel Jacobowitz
 > MontaVista Software                         Debian GNU/Linux Developer
 
 
 
 -- 
 Daniel Jacobowitz
 MontaVista Software                         Debian GNU/Linux Developer