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From: "jwakely.gcc at gmail dot com" <sourceware-bugzilla@sourceware.org>
To: gdb-prs@sourceware.org
Subject: [Bug symtab/14441] Need to support DW_TAG_rvalue_reference_type
Date: Sun, 16 Nov 2014 17:38:00 -0000	[thread overview]
Message-ID: <bug-14441-4717-Ndkw6tORFU@http.sourceware.org/bugzilla/> (raw)
In-Reply-To: <bug-14441-4717@http.sourceware.org/bugzilla/>

https://sourceware.org/bugzilla/show_bug.cgi?id=14441

--- Comment #6 from Jonathan Wakely <jwakely.gcc at gmail dot com> ---
I can live with printing rvalue refs as <unknown type in /dev/shm/a.out, CU
0x0, DIE 0x4b> but the fact you're unable to do anything with them is a much
bigger problem:

struct A { int i; };

int f(A&& a)
{
  return a.i;
}

int main()
{
  return f( A() );
}

Reading symbols from ./a.out...done.
(gdb) start
Temporary breakpoint 1 at 0x4005de: file rv.cc, line 10.
Starting program: /tmp/a.out

Temporary breakpoint 1, main () at rv.cc:10
(gdb) step
f(A&&) (a=<unknown type in /tmp/a.out, CU 0x0, DIE 0x7f>) at rv.cc:5
(gdb) p a.i
Attempt to extract a component of a value that is not a structure.

This makes it almost impossible to debug functions taking rvalues, such as move
constructors and move assignment operators.

And sometimes move constructors are really hard to get right and need to be
debugged (e.g. std::stringstream is giving me major headaches)

-- 
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  parent reply	other threads:[~2014-11-16 17:38 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-08-07 22:00 [Bug symtab/14441] New: " dje at google dot com
2012-08-08  8:10 ` [Bug symtab/14441] " nicholas at mxc dot ca
2012-08-08 16:01 ` tromey at redhat dot com
2012-10-28 13:56 ` jwakely.gcc at gmail dot com
2012-10-28 14:04 ` jwakely.gcc at gmail dot com
2013-06-12 21:24 ` emaste at freebsd dot org
2013-10-14 16:27 ` jan.kratochvil at redhat dot com
2013-10-14 16:30 ` jan.kratochvil at redhat dot com
2013-10-14 16:31 ` jan.kratochvil at redhat dot com
2014-11-16 17:38 ` jwakely.gcc at gmail dot com [this message]
2015-03-10 14:08 ` tohava at gmail dot com

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