[Gdb] gdb segfaults at generic_elf_osabi_sniffer

[Paul Gray]

I've recently seen problems with the functionality of gdb when working
with gcc-3.3 and gcc-3.2 executables.

Specifically, when gdb tries to load in the binary or a core, I'll get the
usual gdb splash screen, followed by an immediate segfault.  Loading gdb
without arguments causes no problems, but when you specify the file;
it will segfault.

So, I did ran gdb on the core that gdb leaves when it segfaults and found
the following:

Loaded symbols for /lib/libm.so.6
Reading symbols from /lib/libdl.so.2...done.
Loaded symbols for /lib/libdl.so.2
Reading symbols from /lib/libc.so.6...done.
Loaded symbols for /lib/libc.so.6
Reading symbols from /lib/ld-linux.so.2...done.
Loaded symbols for /lib/ld-linux.so.2
Reading symbols from /lib/libthread_db.so.1...done.
Loaded symbols for /lib/libthread_db.so.1
#0  0x080e73ce in generic_elf_osabi_sniffer ()
(gdb) where
#0  0x080e73ce in generic_elf_osabi_sniffer ()
#1  0x080e7066 in gdbarch_lookup_osabi ()
#2  0x080e9bac in i386_gdbarch_init ()
#3  0x080b706b in gdbarch_update_p ()
#4  0x080b7c53 in set_gdbarch_from_file ()
#5  0x080cec88 in exec_file_attach ()
#6  0x080df135 in do_captured_command ()
#7  0x080df0df in do_catch_errors ()
#8  0x080df050 in catcher ()
#9  0x080df115 in catch_errors ()
#10 0x080df171 in catch_command_errors ()
#11 0x08072e60 in captured_main ()
#12 0x080df0df in do_catch_errors ()
#13 0x080df050 in catcher ()
#14 0x080df115 in catch_errors ()
#15 0x08072f24 in gdb_main ()
#16 0x0807256a in main ()
#17 0x40099a51 in __libc_start_main () from /lib/libc.so.6

gdb was built with gcc 3.2.3
gdb was configured with:
--prefix=$(prefix) --exec_prefix=$(exec_prefix) --bindir=$(bindir)
--sbindir=$(sbindir) --libexecdir=$(libexecdir) --datadir=$(datadir)
--sysconfdir=$(sysconfdir) --sharedstatedir=$(sharedstatedir)
--localstatedir=$(localstatedir) --libdir=$(libdir) --infodir=$(infodir)
--lispdir=$(lispdir) --includedir=$(includedir) --mandir=$(mandir)
--build=i386-linux --host=i386-pc-linux-gnu --enable-threads --with-shared

with the above variables (prefix, exec_prefix, et. al.) appropriately and
properly defined for the build system.

Any suggestions on a cause or a work-around?


Paul Gray                                         -o)
323 Wright Hall                                   /\\
University of Northern Iowa                      _\_V
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