Datasheet

ManualsBrandsARM ManualsComputer HardwareVERSION 1.2

100

The C and C++ Libraries

The functions listed in Table 4-3 depend indirectly on one or more of the functions

listed in Table 4-2 on page 4-9.

Avoiding the semihosting SWI

If you write an application in C, you must link it with the C library even if it makes no

direct use of C library functions. The C library contains compiler helper functions and

initialization code. Some C library functions use the semihosting SWI. To avoid using

the semihosting SWI, do either of the following:

• re-implement the functions in your own application

• write the application so that it does not call any semihosted function.

To guarantee that no functions using the semihosting SWI are included in your

application, use either:

•

IMPORT __use_no_semihosting_swi

from assembly language

•

#pragma import(__use_no_semihosting_swi)

from C.

The symbol has no effect except to cause a link-time error if a function that uses the

semihosting SWI is included from the library. The linker error message is:

Error : L6200E: Symbol __semihosting_swi_guard multiply defined

(by use_semi.o and use_no_semi.o).

Table 4-3 Indirect dependencies

Function Where used

__raise()

Catch, handle, or diagnose C library exceptions, without C

signal support. See Tailoring error signaling, error handling,

and program exit on page 4-51.

__default_signal_handler()

Catch, handle, or diagnose C library exceptions, with C signal

support. See Tailoring error signaling, error handling, and

program exit on page 4-51.

__Heap_Initialize()

Choosing or redefining memory allocation. See Tailoring

storage management on page 4-57.

ferror()

fputc()

__stdout

Retargeting the printf family. See Tailoring the input/output

functions on page 4-75.

__backspace()

fgetc()

__stdin

Retargeting the scanf family. See Tailoring the input/output

functions on page 4-75.

fwrite()

fputs()

puts()

fread()

fgets()

gets()

ferror()

Retargeting the stream output family. See Tailoring the

input/output functions on page 4-75.