RealView Compilation Tools Compiler Reference Guide - ARM ...

Language Extensions
Example
class B;
class A
{
friend B; // is the same as "friend class B"
};
See also
• --[no_]strict on page 2-84.
3.5.4 Read/write constants
A linkage specification for external constants indicates that a constant can be
dynamically initialized or have mutable members.
Note
The use of "C++:read/write" linkage is only necessary for code compiled with --apcs
/rwpi. If you recompile existing code with this option, you must change the linkage
specification for external constants that are dynamically initialized or have mutable
members.
Compiling C++ with the --apcs /rwpi option deviates from the ISO C++ Standard. The
declarations in Example 3-1 assume that x is in a read-only segment.
Example 3-1 External access
extern const T x;
extern "C++" const T x;
extern "C" const T x;
Dynamic initialization of x including user-defined constructors is not possible for
constants and T cannot contain mutable members. The new linkage specification in
Example 3-2 on page 3-17 declares that x is in a read/write segment even if it is
initialized with a constant. Dynamic initialization of x is permitted and T can contain
mutable members. The definitions of x, y, and z in another file must have the same
linkage specifications.
3-16 Copyright © 2007, 2010 ARM Limited. All rights reserved. ARM DUI 0348A
Non-Confidential