undefined symbol: __dso_handle with current CVS breaks C++

Mon Apr 10 16:02:00 GMT 2000

> This bug is complex to explain, but the fix is very simple.

I'm not so sure it is that simple, though. Did you try building -fPIC
shared libraries containing hidden symbols with that patch?

I'll include a test case which I can't get to work with your patch. It
is important that the patched assembler and linker is used in each
compilation step; you may need to adapt the Makefile. If I made some
error in the code, please let me know. Essentially, this builds a
shared library which exports a function, which in turn calls a hidden
function. On my glibc 2.1.3 installation, this crashes in the dynamic
linker. readelf reports for the shared library

Relocation section '.rel.plt' at offset 0x5b8 contains 5 entries:
  Offset    Info  Type            Symbol's Value  Symbol's Name
  0000186c  01807 R_386_JUMP_SLOT       00000000  atexit                   
  00001870  01b07 R_386_JUMP_SLOT       00000000  __register_frame_info    
  00001874  01e07 R_386_JUMP_SLOT       00000000  __deregister_frame_info  
  00001878  ffffff07 R_386_JUMP_SLOT       bad symbol index: 00ffffff
  0000187c  02707 R_386_JUMP_SLOT       00000000  __gmon_start__

My guess is that the "bad symbol index" is causing the ld.so crash;
this is the PLT slot for the hidden symbol. It may be possible to make
this work like hiding mechanism in symbol versioning, but that appears
to be more complex.

Anyway, please let me know what you find.

Regards,
Martin

#!/bin/sh
# This is a shell archive (produced by GNU sharutils 4.2).
# To extract the files from this archive, save it to some FILE, remove
# everything before the `!/bin/sh' line above, then type `sh FILE'.
#
# Made on 2000-04-11 00:48 CEST by <martin@mira>.
# Source directory was `/home/martin/tmp/hidden'.
#
# Existing files will *not* be overwritten unless `-c' is specified.
#
# This shar contains:
# length mode       name
# ------ ---------- ------------------------------------------
#     47 -rw-rw-r-- exporter.c
#     75 -rw-rw-r-- importer.c
#     81 -rw-rw-r-- main.c
#    667 -rw-rw-r-- Makefile
#
save_IFS="${IFS}"
IFS="${IFS}:"
gettext_dir=FAILED
locale_dir=FAILED
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done
IFS="$save_IFS"
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then
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  $echo 'WARNING: not restoring timestamps.  Consider getting and'
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fi
rm -f 1231235999 $$.touch
#
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fi
rm -fr _sh05571
exit 0