55 lines
1.7 KiB
Plaintext
55 lines
1.7 KiB
Plaintext
PURPOSE of /tools/glibc/Regression/bz689471-SSE4-strncmp-failure
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Description: Test for bz689471 (SSE4 strncmp failure)
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Author: Miroslav Franc <mfranc@redhat.com>
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Bug summary: SSE4 strncmp failure
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Bugzilla link: https://bugzilla.redhat.com/show_bug.cgi?id=689471
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Description:
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H.J. Lu 2011-03-21 05:42:34 CET
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On Intel Core i7, I got
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[hjl@gnu-6 997]$ cat saved.c
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sys/mman.h>
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int main()
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{
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char *buf, *buf2;
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buf = (char*)mmap((void*)0x100000000, 0x2000 * 2,
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PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
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buf = mmap((char *)buf, 0x2000, PROT_READ | PROT_WRITE,
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MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
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memset(buf, 'a', 0x2000);
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buf[0x1fff] = 0;
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buf2 = strdup(buf);
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if (strncmp (buf + 3994, buf2 + 2635, 6241) >= 0)
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abort ();
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return 0;
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}
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[hjl@gnu-6 997]$ gcc saved.c
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[hjl@gnu-6 997]$ ./a.out
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Segmentation fault
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[hjl@gnu-6 997]$ gdb a.out
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GNU gdb (GDB) 7.2.50.20110312-cvs
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Copyright (C) 2011 Free Software Foundation, Inc.
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License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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This is free software: you are free to change and redistribute it.
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There is NO WARRANTY, to the extent permitted by law. Type "show copying"
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and "show warranty" for details.
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This GDB was configured as "x86_64-unknown-linux-gnu".
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For bug reporting instructions, please see:
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<http://www.gnu.org/software/gdb/bugs/>...
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Reading symbols from /export/home/hjl/bugs/libc/997/a.out...(no debugging
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symbols found)...done.
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(gdb) r
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Starting program: /export/home/hjl/bugs/libc/997/a.out
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Program received signal SIGSEGV, Segmentation fault.
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0x0000003f7d3214a0 in __strncmp_sse42 () from /lib64/libc.so.6
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(gdb)
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