The linker performs smart linking - in that it strips the symbols that are not actually used. This means that only the library routines that are used will be allocated to section .text. In order to see which exactly these routines are, check the object allocation section in the .map.file, looking for object files pertaining to the library, e.g.:
*********************************************************************************************
OBJECT-ALLOCATION SECTION
Name Module Addr hSize dSize Ref Section RLIB
---------------------------------------------------------------------------------------------
...
MODULE: -- RTSHC08.C.o (ansifs.lib) --
- PROCEDURES:
_PUSH_ARGS_L 2146 20 32 1 .text
_ENTER_BINARY_L 2166 16 22 2 .text
...
_FMUL 244D 7 7 1 .text
_FDIV 2454 7 7 1 .text
You will not see any of the not used procedures listed under the object allocation section.
If you sum up all the sizes (decimal: dSize) associated with section .text in the object allocation section, you obtain the size of .text as listed in the section allocation section of the map file.