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Hi, |
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|
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since the last system upgrade I always get floating point exceptions when I |
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start self compiled programs or during configure steps (once the gcc compiler |
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is tested). After some searching I found that ld --hash-style= option is the |
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reason. Some time ago a new "gnu" method was introduced to speed loading of |
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dynamic libraries up. |
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|
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The problem I have is that glibc uses still the old sysv hash whereas |
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gcc (or/and ld) defaults to gnu. Using -Wl,--hash-style=sysv in CFLAGS, |
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CXXFLAGS and LDFLAGS improves the situation as I can now continue |
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compiling C (but no C++) programs. I rebuild gcc (4.1.2), glibc (2.3.6-r5) |
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and binutils (2.18-r1) but it did not helped. |
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|
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I assumed that --hash_style=both is the new toolchain default and would put |
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both old hash and new gnu_hash into binaries and would allow me linking against |
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my glibc (which still uses old hash). But I was wrong: |
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|
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$ mips-unknown-linux-gnu-gcc -Wl,--hash-style=sysv main.c |
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$ ./a.out |
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Hello world |
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$ mips-unknown-linux-gnu-gcc -Wl,--hash-style=both main.c |
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$ ./a.out |
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Floating point exception |
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$ mips-unknown-linux-gnu-gcc -Wl,--hash-style=gnu main.c |
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$ ./a.out |
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Floating point exception |
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|
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With sysv I get: |
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$ readelf -a a.out | grep -i hash |
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[ 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 |
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0x00000004 (HASH) 0x4002ac |
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|
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and with gnu and both I get the same output: |
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$ cat /tmp/readelf.both |
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[ 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 |
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0x6ffffef5 (GNU_HASH) 0x4002ac |
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1: 00000000 0 FUNC WEAK DEFAULT [GNUHASH] UND __gmon_start__ |
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2: 00000000 0 NOTYPE WEAK DEFAULT [GNUHASH] UND _Jv_RegisterClasses |
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3: 00400860 476 FUNC GLOBAL DEFAULT [GNUHASH] UND puts@GLIBC_2.0 (2) 5: 0040075c 128 FUNC GLOBAL DEFAULT [GNUHASH] 11 __libc_csu_init |
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7: 00400680 88 FUNC GLOBAL DEFAULT [GNUHASH] 11 main |
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8: 0040049c 0 FUNC GLOBAL DEFAULT [GNUHASH] 10 _init |
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9: 004006e0 124 FUNC GLOBAL DEFAULT [GNUHASH] 11 __libc_csu_fini |
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11: 00400880 0 FUNC GLOBAL DEFAULT [GNUHASH] 13 _fini |
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12: 00400850 308 FUNC GLOBAL DEFAULT [GNUHASH] UND __libc_start_main@GLIBC_2.0 (2) |
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34: 004006e0 124 FUNC GLOBAL DEFAULT [GNUHASH] 11 __libc_csu_fini |
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37: 00000000 0 FUNC WEAK DEFAULT [GNUHASH] UND __gmon_start__ |
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38: 00000000 0 NOTYPE WEAK DEFAULT [GNUHASH] UND _Jv_RegisterClasses |
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39: 00400880 0 FUNC GLOBAL DEFAULT [GNUHASH] 13 _fini |
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41: 00400850 308 FUNC GLOBAL DEFAULT [GNUHASH] UND __libc_start_main@@GLIBC_ |
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47: 0040075c 128 FUNC GLOBAL DEFAULT [GNUHASH] 11 __libc_csu_init |
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52: 00400860 476 FUNC GLOBAL DEFAULT [GNUHASH] UND puts@@GLIBC_2.0 |
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55: 00400680 88 FUNC GLOBAL DEFAULT [GNUHASH] 11 main |
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56: 0040049c 0 FUNC GLOBAL DEFAULT [GNUHASH] 10 _init |
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Histogram for `.gnu.hash' bucket list length (total of 3 buckets): |
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|
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This shows that --hash-style=both is identical to --hash-style=gnu and not |
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properly working on my system. Why? |
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|
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I found also an article about hash style in the Gentoo Wiki and tried |
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rebuilding my toolchain with USE=hashstyle but this did not helped. |
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|
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Any ideas? Is this a known error on Mips (o32 ABI)? |
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|
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Jens |
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-- |
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