Red Hat ENTERPRISE LINUX 4 - DEVELOPER TOOLS GUIDE, Руководство пользователя

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Chapter 17. gdb Files 147
0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b,
0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1,
0x18b74777, 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45, 0xa00ae278,
0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7,
0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 0x40df0b66,
0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605,
0xcdd70693, 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8,
0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b,
0x2d02ef8d
};
unsigned char *end;
crc = ~crc & 0xffffffff;
for (end = buf + len; buf
@
end; ++buf)
crc = crc32_table[(crc ^ *buf) & 0xff] ^ (crc
AA
8);
return ~crc & 0xffffffff;
}
17.3. Errors reading symbol files
While reading a symbol file, gdb occasionally encounters problems, such as symbol types it does not
recognize, or known bugs in compiler output. By default, gdb does not notify you of such problems,
since they are relatively common and primarily of interest to people debugging compilers. If you are
interested in seeing information about ill-constructed symbol tables, you can either ask gdb to print
only one message about each such type of problem, no matter how many times the problem occurs;
or you can ask gdb to print more messages, to see how many times the problems occur, with the
set
complaints
command (refer to Section 21.7 Optional warnings and messages ).
The messages currently printed, and their meanings, include:
inner block not inside outer block in
symbol
The symbol information shows where symbol scopes begin and end (such as at the start of a
function or a block of statements). This error indicates that an inner scope block is not fully
contained in its outer scope blocks.
gdb circumvents the problem by treating the inner block as if it had the same scope as the outer
block. In the error message,
symbol
may be shown as "
(don’t know)
" if the outer block is not
a function.
block at
address
out of order
The symbol information for symbol scope blocks should occur in order of increasing addresses.
This error indicates that it does not do so.
gdb does not circumvent this problem, and has trouble locating symbols in the source file whose
symbols it is reading. (You can often determine what source file is affected by specifying
set
verbose on
. Refer to Section 21.7 Optional warnings and messages .)
bad block start address patched
The symbol information for a symbol scope block has a start address smaller than the address of
the preceding source line. This is known to occur in the SunOS 4.1.1 (and earlier) C compiler.
gdb circumvents the problem by treating the symbol scope block as starting on the previous
source line.