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<div class="moz-text-flowed" style="font-family: -moz-fixed;
font-size: 13px;" lang="x-western">Hi,
<br>
<br>
On 2021-02-02 18:47, Christo Crause wrote:
<br>
<blockquote type="cite" style="color: #007cff;">On Tue, Feb 2,
2021 at 12:28 PM Dimitrios Chr. Ioannidis via fpc-devel
<br>
<a class="moz-txt-link-rfc2396E"
href="mailto:fpc-devel@lists.freepascal.org"><fpc-devel@lists.freepascal.org></a>
wrote:
<br>
<br>
<blockquote type="cite" style="color: #007cff;">Reading dwarf
information with avr-embedded-objdump.exe --dwarf
<br>
returns
<br>
: "avr-embedded-objdump.exe: Warning: Invalid CIE pointer
0x00c80000
<br>
in
<br>
FDE at 0x000014"
<br>
</blockquote>
<br>
I get the same warning on Linux using avr-objdump (GNU objdump
(GNU
<br>
Binutils) 2.26.20160125), your test code and all of the dwarf
debug
<br>
options in the compiler. Not sure if this is really a problem
when
<br>
debugging with gdb, I've managed to debug across units before.
Do you
<br>
have a reproducible problematic debug situation that can be
tested?
<br>
</blockquote>
<br>
I checked with the dwarf 2.o specification and I read that "in
FDE (Frame Description Entry) there is a CIE_pointer field which
is a uword constant offset into the .debug_frame section that
denotes the CIE that is associated with this FDE."
<br>
<br>
<br>
AFAIU, both are used, among others of course, to provide virtual
unwind information to debugger . But here there is a problem, IMO,
the FDE has an CIE_id of fd39e538 but there is none CIE with that
id. There is only one CIE with id ffffffff .
<br>
<br>
<br>
"dwarf_CIE_FDE_Bug.elf: file format elf32-avr
<br>
<br>
Contents of the .debug_frame section:
<br>
<br>
<br>
00000000 0010 ffffffff CIE
<br>
Version: 1
<br>
Augmentation: ""
<br>
Code alignment factor: 1
<br>
Data alignment factor: -4
<br>
Return address column: 24
<br>
<br>
DW_CFA_def_cfa: r32 ofs 2
<br>
DW_CFA_offset_extended: r36 at cfa+0
<br>
DW_CFA_nop
<br>
<br>
00000014 0000 00c80000 FDE cie=fd39e538 pc=0002..0002"
<br>
<br>
<br>
Of course I maybe be wrong and this is not a problem.
<br>
<br>
regards,
<br>
<br>
<div class="moz-txt-sig"><span class="moz-txt-tag">-- <br>
</span>Dimitrios Chr. Ioannidis
<br>
<br>
</div>
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