Compiler Calls to Built-In Functions

[Fusillade]

How does the compiler process calls to the built in functions? For instance, if I call clear_interrupt() or input_state() in my main program AND in my interrupt routine, should I:

- receive a warning from the compiler telling me that I've made a call to a function that could be in use?

- not receive an error because the compiler creates a secondary instance of the function for interrupt purposes?

- not receive an error because the command is not really a function but a macro and code substitution is used?

- or is everything designed such that the function can be interrupted and called again during the interrupt without causing corruption issues?

I just want to make sure that there is no chance of unexpected data corruption during my interrupt routines.
_________________
New:

Compiler Version: 5.078
IDE Version: MPLAB X V4.15
Devices: PIC18LF****

Old:

Compiler Version: 4.121
IDE Version: MPLAB IDE V8.63
Devices: PIC18LF****

[PCM programmer]

See this FAQ article:
http://www.ccsinfo.com/faq.php?page=interrupts_disabled

[Fusillade]

So if I call the CCS supplied clear_interrupt() function outside of the interrupt and inside of the interrupt and I do not get a warning message from the compiler, then I should have no problems even if the clear_interrupt function is the process which is interrupted?
_________________
New:

Compiler Version: 5.078
IDE Version: MPLAB X V4.15
Devices: PIC18LF****

Old:

Compiler Version: 4.121
IDE Version: MPLAB IDE V8.63
Devices: PIC18LF****

[PCM programmer]

The clear_interrupt() function will generate one line of ASM code.
It's never going created as a separate routine by the compiler.
The compiler will always insert the ASM code as an inline statement
every time it sees that function.

[Fusillade]

Taking what you have told me and running with it, I've come to the following conclusion.

All CCS functions that do not require a library will use code substitution (inserting a single or multiple lines of assembly code in place of the function) and all other functions which require a library will generate a call. Any of the functions which require a call and are used in both the main program and the interrupts are likely to generate the warning message. So as long as I avoid functions which require a library, then I should be safe.
_________________
New:

Compiler Version: 5.078
IDE Version: MPLAB X V4.15
Devices: PIC18LF****

Old:

Compiler Version: 4.121
IDE Version: MPLAB IDE V8.63
Devices: PIC18LF****

[PCM programmer]

Or invoke the library a 2nd time, to generate another instance of it.
See this FAQ article:
http://www.ccsinfo.com/faq.php?page=delay_in_interrupt

[Fusillade]

Thanks for all your help.

I've been burned in the past because of the way some C compilers process certain commands and so I tend to be a bit cautious. What can I say, I like it best when there are no surprises.
_________________
New:

Compiler Version: 5.078
IDE Version: MPLAB X V4.15
Devices: PIC18LF****

Old:

Compiler Version: 4.121
IDE Version: MPLAB IDE V8.63
Devices: PIC18LF****