summary: Test for bz689471 (SSE4 strncmp failure) description: | Bug summary: SSE4 strncmp failure Bugzilla link: https://bugzilla.redhat.com/show_bug.cgi?id=689471 Description: H.J. Lu 2011-03-21 05:42:34 CET On Intel Core i7, I got [hjl@gnu-6 997]$ cat saved.c #include #include #include #include int main() { char *buf, *buf2; buf = (char*)mmap((void*)0x100000000, 0x2000 * 2, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); buf = mmap((char *)buf, 0x2000, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0); memset(buf, 'a', 0x2000); buf[0x1fff] = 0; buf2 = strdup(buf); if (strncmp (buf + 3994, buf2 + 2635, 6241) >= 0) abort (); return 0; } [hjl@gnu-6 997]$ gcc saved.c [hjl@gnu-6 997]$ ./a.out Segmentation fault [hjl@gnu-6 997]$ gdb a.out GNU gdb (GDB) 7.2.50.20110312-cvs Copyright (C) 2011 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-unknown-linux-gnu". For bug reporting instructions, please see: ... Reading symbols from /export/home/hjl/bugs/libc/997/a.out...(no debugging symbols found)...done. (gdb) r Starting program: /export/home/hjl/bugs/libc/997/a.out Program received signal SIGSEGV, Segmentation fault. 0x0000003f7d3214a0 in __strncmp_sse42 () from /lib64/libc.so.6 (gdb) contact: Miroslav Franc component: - glibc test: ./runtest.sh framework: beakerlib recommend: - glibc - gcc duration: 15m link: - relates: https://bugzilla.redhat.com/show_bug.cgi?id=689471 extra-summary: /tools/glibc/Regression/bz689471-SSE4-strncmp-failure extra-task: /tools/glibc/Regression/bz689471-SSE4-strncmp-failure