public inbox for
 help / color / mirror / Atom feed
* Issue in dwarf2/expr.c
@ 2022-04-13 16:57 Rohr, Stephan
  2022-04-14 13:51 ` Andreas Arnez
  0 siblings, 1 reply; 4+ messages in thread
From: Rohr, Stephan @ 2022-04-13 16:57 UTC (permalink / raw)
  To: gdb

Hi all,

I came across a bug in dwarf2/expr.c:177 in function  rw_pieced_value. when reading a pieced value described by DW_OP_piece or DW_OP_bit_piece.

      if (value_type (v) != value_enclosing_type (v))
                internal_error (__FILE__, __LINE__,
                                                _("Should not be able to create a lazy value with "
                                                  "an enclosing type"));

This check can easily be triggered when casting a variable with location described by DW_OP_piece or DW_OP_bit_piece.

A minimal reproducer can be found in gdb/testsuite/gdb.dwarf2/shortpiece.exp, e.g. casting s1 to an array type triggers the error

p (short []) s1

I currently struggle to understand the reasoning for this check. I could think of changing this to

if (TYPE_LENGTH(value_type (v)) > TYPE_LENGTH( value_enclosing_type (v)))
to support the cast operation.

But in general, I'm not sure why this check is needed at all.

I appreciate your feedback.


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2022-04-19  6:28 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-04-13 16:57 Issue in dwarf2/expr.c Rohr, Stephan
2022-04-14 13:51 ` Andreas Arnez
2022-04-15 20:24   ` Tom Tromey
2022-04-19  6:28     ` Rohr, Stephan

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).