| |||
| Home > The ARM C and C++ libraries > Using the libraries in a nonsemihosting environment | |||
Some C library functions use semihosting. If you do not want to use semihosting, either:
Remove all calls to semihosting functions.
Re-implement the lower-level functions, for example, fputc().
You are not required to re-implement all semihosting functions.
You must, however, re-implement the functions you are using in your
application.
(You must re-implement functions that the C library uses to
isolate itself from target dependencies. For example, if you use printf() you
must re-implement fputc(). If you do not use
the higher-level input/output functions like printf(),
you do not have to re-implement the lower-level functions like fputc().
)
Implement a handler for all of the semihosting calls to be handled in your own specific way. One such example is for the handler to intercept the calls, redirecting them to your own nonsemihosted, that is, target-specific, functions.
To guarantee that no functions using semihosting are included in your application, use either:
IMPORT __use_no_semihosting from assembly
language
#pragma import(__use_no_semihosting) from
C.
IMPORT __use_no_semihosting is only required
to be added to a single assembly source file. Similarly, #pragma
import(__use_no_semihosting) is only required to be added
to a single C source file. It is unnecessary to add these inserts
to every single source file.
If you include a library function that uses semihosting and
also reference __use_no_semihosting, the
library detects the conflicting symbols and the linker reports an
error. To determine which objects are using semihosting:
link with --verbose
--list=out.txt
search the output for the symbol
determine what object referenced it.
There are no target-dependent functions in the C++ library, although some C++ functions use underlying C library functions that are target-dependent.