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llvm-nm - list LLVM bitcode and object file's symbol table

SYNOPSIS

:program:`llvm-nm` [options] [filenames...]

DESCRIPTION

The :program:`llvm-nm` utility lists the names of symbols from LLVM bitcode files, object files, and archives. Each symbol is listed along with some simple information about its provenance. If no filename is specified, a.out is used as the input. If - is used as a filename, :program:`llvm-nm` will read a file from its standard input stream.

:program:`llvm-nm`'s default output format is the traditional BSD :program:`nm` output format. Each such output record consists of an (optional) 8-digit hexadecimal address, followed by a type code character, followed by a name, for each symbol. One record is printed per line; fields are separated by spaces. When the address is omitted, it is replaced by 8 spaces.

The supported type code characters are as follows. Where both lower and upper-case characters are listed for the same meaning, a lower-case character represents a local symbol, whilst an upper-case character represents a global (external) symbol:

a, A

Absolute symbol.

b, B

Unitialized data (bss) object.

C

Common symbol. Multiple definitions link together into one definition.

d, D

Writable data object.

i, I

COFF: .idata symbol or symbol in a section with IMAGE_SCN_LNK_INFO set.

n

ELF: local symbol from non-alloc section.

COFF: debug symbol.

N

ELF: debug section symbol, or global symbol from non-alloc section.

s, S

COFF: section symbol.

Mach-O: absolute symbol or symbol from a section other than __TEXT_EXEC __text, __TEXT __text, __DATA __data, or __DATA __bss.

r, R

Read-only data object.

t, T

Code (text) object.

u

ELF: GNU unique symbol.

U

Named object is undefined in this file.

v

ELF: Undefined weak object. It is not a link failure if the object is not defined.

V

ELF: Defined weak object symbol. This definition will only be used if no regular definitions exist in a link. If multiple weak definitions and no regular definitons exist, one of the weak definitions will be used.

w

Undefined weak symbol other than an ELF object symbol. It is not a link failure if the symbol is not defined.

W

Defined weak symbol other than an ELF object symbol. This definition will only be used if no regular definitions exist in a link. If multiple weak definitions and no regular definitons exist, one of the weak definitions will be used.

-

Mach-O: N_STAB symbol.

?

Something unrecognizable.

Because LLVM bitcode files typically contain objects that are not considered to have addresses until they are linked into an executable image or dynamically compiled "just-in-time", :program:`llvm-nm` does not print an address for any symbol in an LLVM bitcode file, even symbols which are defined in the bitcode file.

OPTIONS

MACH-O SPECIFIC OPTIONS

BUGS

EXIT STATUS

:program:`llvm-nm` exits with an exit code of zero.