符号类型.
小写字母表示局部; 大写字母表示全局(外部).
A
The symbol's value is absolute, and will not be changed by further linking.
B
The symbol is in the uninitialized data section (known as BSS).
C
The
symbol is common. Common symbols are uninitialized data. When linking,
multiple common symbols may appear with the same name. If the symbol is
defined anywhere, the common symbols are treated as undefined
references. For more details on common symbols, see the discussion of
-warn-common in Linker options.
D
The symbol is in the initialized data section.
G
The
symbol is in an initialized data section for small objects. Some object
file formats permit more efficient access to small data objects, such
as a global int variable as opposed to a large global array.
I
The
symbol is an indirect reference to another symbol. This is a GNU
extension to the a.out object file format which is rarely used.
N
The symbol is a debugging symbol.
R
The symbol is in a read only data section.
S
The symbol is in an uninitialized data section for small objects.
T
The symbol is in the text (code) section.
U
The symbol is undefined.
V
The
symbol is a weak object. When a weak defined symbol is linked with a
normal defined symbol, the normal defined symbol is used with no error.
When a weak undefined symbol is linked and the symbol is not defined,
the value of the weak symbol becomes zero with no error.
W
The
symbol is a weak symbol that has not been specifically tagged as a weak
object symbol. When a weak defined symbol is linked with a normal
defined symbol, the normal defined symbol is used with no error. When a
weak undefined symbol is linked and the symbol is not defined, the
value of the weak symbol becomes zero with no error.
-
The
symbol is a stabs symbol in an a.out object file. In this case, the
next values printed are the stabs other field, the stabs desc field,
and the stab type. Stabs symbols are used to hold debugging
information. For more information, see Stabs.
?
The symbol type is unknown, or object file format specific.