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Date: Wed, 5 Dec 2012 12:13:24 +0530
Message-ID: <CAEOAkMU0osWoUensNaqBH+PWP9bcTLZffwLVh3WeppzqKMmT0g@mail.gmail.com>
Subject: ELF symtab and ddbsymtab difference
From: Shrikanth Kamath <shrikanth07@gmail.com>
To: freebsd-hackers@freebsd.org
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This is regarding the fields in the structure "elf_file_t" in link_elf.c.
For some kernel modules the symtab field is different from the ddbsymtab
field for some it is the same, would like to know what is the difference
between the two and how to enable ddbsymtab?

Does enabling "-g" in CFLAGS make the binary build the ddbsymtab different
from symtab?

The problem is lookup for some symbols in the kernel module that I built
returns with undefined, on inspecting it was getting a ENOENT from the
function
    link_elf_lookup_symbol()
    {
         ...
         /* If we have not found it, look at the full table (if loaded) */
         if (ef->symtab == ef->ddbsymtab)
             return (ENOENT);
         ...
    }

--
Shrikanth R K