Re: [PATCH] [PR 25678] gdb crashes with "internal-error: sect_index_text not initialized" when .text

mlimber
2020-05-20T13:24:56Z

On Tue, May 19, 2020 at 10:50 AM Simon Marchi <simark@simark.ca> wrote:

> Are we inspecting the same library? In the libicudata.so.52 you've sent,
> there
> are three load segments:
>
> $ readelf -l libicudata.so.52.2 | grep LOAD
> LOAD 0x000000 0x0000000000000000 0x0000000000000000 0x166a940
> 0x166a940 R 0x200000
> LOAD 0x166af30 0x000000000186af30 0x000000000186af30 0x0000d0
> 0x0000d0 RW 0x200000
> LOAD 0x166c000 0x000000000186b000 0x000000000186b000 0x000180
> 0x000180 RW 0x1000
>

Ah, my bad. The lib freshly rebuilt from source has two segments, but the
one I uploaded has three because I manually set the RPATH on it. (The data
lib doesn't really need to be on this since it doesn't have other
dependencies, but it just got caught up in a glob of all the ICU libs.)

So the additional step needed after building from source is to run
`patchelf --set-rpath \$ORIGIN libicudata.so.52.2`.

To reduce confusion (maybe), I have added two files to the same dropbox
folder -- libicudata-unpatched.so.52.2 and libicudata-with-rpath.so.52.2.
(I have left the original files I uploaded there for now.)

(For my own application, I have rebuilt libicu* again after running
`./configure --enable-rpath=yes`, and then I get the RPATHs I need so I
don't need the patchelf at all. Thus my app's problem is resolved.)

> I successfully reproduced the bug using your lib. Since there's no DWARF
> info, it fails in init_entry_point_info. With my lib, it fails earlier,
> when the DWARF info is read. Anyway, it's all variations of the same bug,
> some code assumes that sect_index_text is set to some valid value.<
>

I can now also repro the original bug in a rinky-dink program suitable for
unit testing. Can you supply the steps to build a small program to repro
the DWARF-related bug?

Will both bugs be fixed by a change in one place? That is, is my second
patch irrelevant because we'll ultimately fix both bugs at some higher
level? If the patch is still valid, I could work to submit an updated patch
and test case for my non-DWARF bug now, and then you (or you and I) can
work up a test case and fix -- possibly under a new bug ticket -- for the
DWARF bug.

M