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Hi,

since the last system upgrade I always get floating point exceptions when I
start self compiled programs or during configure steps (once the gcc compiler
is tested). After some searching I found that ld --hash-style= option is the
reason. Some time ago a new "gnu" method was introduced to speed loading of
dynamic libraries up.

The problem I have is that glibc uses still the old sysv hash whereas
gcc (or/and ld) defaults to gnu. Using -Wl,--hash-style=sysv in CFLAGS,
CXXFLAGS and LDFLAGS improves the situation as I can now continue
compiling C (but no C++) programs. I rebuild gcc (4.1.2), glibc (2.3.6-r5)
and binutils (2.18-r1) but it did not helped.

I assumed that --hash_style=both is the new toolchain default and would put
both old hash and new gnu_hash into binaries and would allow me linking against
my glibc (which still uses old hash). But I was wrong:

$ mips-unknown-linux-gnu-gcc -Wl,--hash-style=sysv main.c
$ ./a.out
Hello world
$ mips-unknown-linux-gnu-gcc -Wl,--hash-style=both main.c
$ ./a.out
Floating point exception
$ mips-unknown-linux-gnu-gcc -Wl,--hash-style=gnu main.c
$ ./a.out
Floating point exception

With sysv I get:
$ readelf -a a.out | grep -i hash
[ 5] .hash HASH 004002ac 0002ac 000048 04 A 6 0 4 03 .interp .note.ABI-tag .reginfo .dynamic .hash .dynsym .dynstr .gnu.version .gnu.version_r .init .text .MIPS.stubs .fini .rodata .eh_frame
0x00000004 (HASH) 0x4002ac

and with gnu and both I get the same output:
$ cat /tmp/readelf.both
[ 5] .gnu.hash GNU_HASH 004002ac 0002ac 00004c 04 A 6 0 4 03 .interp .note.ABI-tag .reginfo .dynamic .gnu.hash .dynsym .dynstr .gnu.version .gnu.version_r .init .text .MIPS.stubs .fini .rodata .eh_frame
0x6ffffef5 (GNU_HASH) 0x4002ac
1: 00000000 0 FUNC WEAK DEFAULT [GNUHASH] UND __gmon_start__
2: 00000000 0 NOTYPE WEAK DEFAULT [GNUHASH] UND _Jv_RegisterClasses
3: 00400860 476 FUNC GLOBAL DEFAULT [GNUHASH] UND puts@GLIBC_2.0 (2) 5: 0040075c 128 FUNC GLOBAL DEFAULT [GNUHASH] 11 __libc_csu_init
7: 00400680 88 FUNC GLOBAL DEFAULT [GNUHASH] 11 main
8: 0040049c 0 FUNC GLOBAL DEFAULT [GNUHASH] 10 _init
9: 004006e0 124 FUNC GLOBAL DEFAULT [GNUHASH] 11 __libc_csu_fini
11: 00400880 0 FUNC GLOBAL DEFAULT [GNUHASH] 13 _fini
12: 00400850 308 FUNC GLOBAL DEFAULT [GNUHASH] UND __libc_start_main@GLIBC_2.0 (2)
34: 004006e0 124 FUNC GLOBAL DEFAULT [GNUHASH] 11 __libc_csu_fini
37: 00000000 0 FUNC WEAK DEFAULT [GNUHASH] UND __gmon_start__
38: 00000000 0 NOTYPE WEAK DEFAULT [GNUHASH] UND _Jv_RegisterClasses
39: 00400880 0 FUNC GLOBAL DEFAULT [GNUHASH] 13 _fini
41: 00400850 308 FUNC GLOBAL DEFAULT [GNUHASH] UND __libc_start_main@@GLIBC_
47: 0040075c 128 FUNC GLOBAL DEFAULT [GNUHASH] 11 __libc_csu_init
52: 00400860 476 FUNC GLOBAL DEFAULT [GNUHASH] UND puts@@GLIBC_2.0
55: 00400680 88 FUNC GLOBAL DEFAULT [GNUHASH] 11 main
56: 0040049c 0 FUNC GLOBAL DEFAULT [GNUHASH] 10 _init
Histogram for `.gnu.hash' bucket list length (total of 3 buckets):

This shows that --hash-style=both is identical to --hash-style=gnu and not
properly working on my system. Why?

I found also an article about hash style in the Gentoo Wiki and tried
rebuilding my toolchain with USE=hashstyle but this did not helped.

Any ideas? Is this a known error on Mips (o32 ABI)?

Jens
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