Why does adding /usr/lib32 to LD_LIBRARY_PATH break 64-bit binaries?

[Dag-Erling Smørgrav]

Dag-Erling Smørgrav <des at des.no> writes:
> If you look at the rtld(1) man page, there are a number of environment
> variables you can set to debug the loader.  I'm not sure how helpful
> they are, though.

You can rebuild rtld(1) with debugging enabled:

% cd /usr/src/libexec/rtld-elf
% make clean
% make DEBUG_FLAGS=-DDEBUG
% make install
% echo $LD_LIBRARY_PATH 
/home/des/lib:/opt/varnish/lib:/usr/local/lib
% LD_DEBUG=1 /usr/bin/true
/libexec/ld-elf.so.1 is initialized, base address = 0x800500000
RTLD dynamic = 0x8006305b0
RTLD pltgot  = 0x0
processing main program's program header
Filling in DT_DEBUG entry
lm_init("(null)")
loading LD_PRELOAD libraries
loading needed objects
 Searching for "libc.so.7"
  Trying "/home/des/lib/libc.so.7"
  Trying "/opt/varnish/lib/libc.so.7"
  Trying "/usr/local/lib/libc.so.7"
  Trying "/lib/libc.so.7"
loading "/lib/libc.so.7"
Ignoring d_tag 1879048185 = 0x6ffffff9
  0x80063b000 .. 0x80085efff: /lib/libc.so.7
checking for required versions
initializing initial thread local storage
relocating "/usr/bin/true"
relocating "/lib/libc.so.7"
doing copy relocations
initializing key program variables
"__progname": *0x5005e8 <-- 0x7fffffffebc1
"environ": *0x500878 <-- 0x7fffffffe9a8
initializing thread locks
calling init function for /lib/libc.so.7 at 0x800664da8
"__sysctl" in "libc.so.7" ==> 0x80071ae00 in "libc.so.7"
reloc_jmpslot: *0x800845c78 = 0x80071ae00
transferring control to program entry point = 0x400420
"atexit" in "true" ==> 0x8006fac3e in "libc.so.7"
reloc_jmpslot: *0x500868 = 0x8006fac3e
"exit" in "true" ==> 0x8006af118 in "libc.so.7"
reloc_jmpslot: *0x500860 = 0x8006af118
"__cxa_finalize" in "libc.so.7" ==> 0x8006fa940 in "libc.so.7"
reloc_jmpslot: *0x800846140 = 0x8006fa940
rtld_exit()
calling fini function for /lib/libc.so.7 at 0x80071ae60
"_exit" in "libc.so.7" ==> 0x8006cfff0 in "libc.so.7"
reloc_jmpslot: *0x8008471d8 = 0x8006cfff0

DES
-- 
Dag-Erling Smørgrav - des at des.no