Symbol Types

Symbol type is one of the following:

undefined

A value is of undefined symbol type if it has not yet been defined. Example instances of undefined symbol types are forward references and externals.

absolute

A value is of absolute symbol type it does not change with relocation. Example instances of absolute symbol types are numeric constants and expressions whose proper sub-expressions are themselves all absolute.

text

A value is of text symbol type if it is relative to the .text section.

data

A value is of data symbol type if it is relative to the .data section.

bss

A value is of bss symbol type if it is relative to the .bss section.

You can give any of these symbol types the attribute EXTERNAL.