Qualifiers (j.3.10), Declarators (f.3.11 of ansi c standard), Statements (f.3.12 of ansi c standard) – Echelon Neuron C User Manual

Page 256: Preprocessing directives (j.3.11)

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Neuron C Language Implementation Characteristics

Qualifiers (J.3.10)

Q: What constitutes an access to an object that has

volatile

-qualified type? (Sec.

6.7.3)

A:

Neuron C does not support volatile-qualified type. The compiler also produces

a warning diagnostic whenever the volatile qualifier is used.

Declarators (F.3.11 of ANSI C Standard)

Q: What is the maximum number of declarators that can modify an arithmetic,

structure, or union type? (Sec. 3.5.4)

A:

There is no limit to the maximum number of declarators that modify any type.

The limit is determined at run-time by the amount of heap memory and stack
space available to the compiler.

Statements (F.3.12 of ANSI C Standard)

Q: What is the maximum number of

case

values in a

switch

statement? (Sec.

3.6.4.2)

A:

The Neuron C switch statement only accepts an int expression for the switch

value. Because no two case labels in a switch statement can have the same
value, there are only 256 choices permitted. Neuron C accepts all 256 different

case values for a single switch statement.

Preprocessing Directives (J.3.11)

Q: Does the value of a single-character constant in a constant expression that

controls conditional inclusion match the value of the same character constant in

the execution character set? Can such a character constant have a negative

value? (Sec. 6.10.1)

A:

Yes, and yes.

Q: What is the method for locating includable source files? (Sec. 6.10.2)

A:

The normal include directive should use the quoted form. To access the

system

include files, the directive should use the bracketed form.

Example:

#include

<stddef.h>

System include files are defined as the include files installed by the NodeBuilder
Development Tool. They are located in the LonWorks Neuron C\Include

directory (c:\LonWorks\NeuronC\Include by default). With the exception of the

LonWorks directory, the location of the system include files cannot be changed.

Use the following quoted form for all user include files:

#include

"[drive:][pathname\]filename.ext"

The quoted form causes the compiler to use the filename as it stands if it is

absolute or drive-relative. Otherwise, the compiler first searches the working
directory (using a relative pathname if one is supplied). Next, it searches each of

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