RealView Compilation Tools Compiler Reference Guide - ARM ...

C and C++ Implementation Details
5.1 C and C++ implementation details
This section describes language implementation details common to both C and C++.
5.1.1 Character sets and identifiers
The following points apply to the character sets and identifiers expected by the
compiler:
• Uppercase and lowercase characters are distinct in all internal and external
identifiers. An identifier can also contain a dollar ($) character unless the
--strict compiler option is specified. To permit dollar signs in identifiers with the
--strict option, also use the --dollar command-line option.
• Calling setlocale(LC_CTYPE, "ISO8859-1") makes the isupper() and islower()
functions behave as expected over the full 8-bit Latin-1 alphabet, rather than over
the 7-bit ASCII subset. The locale must be selected at link-time. (See Tailoring
locale and CTYPE using C macros on page 2-60 in the Libraries Guide)
• Source files are compiled according to the currently selected locale. You might
have to select a different locale, with the --locale command-line option, if the
source file contains non-ASCII characters. See Invoking the ARM compiler on
page 2-2 in the Compiler User Guide for more information.
• The ARM compiler supports multibyte character sets, such as Unicode.
• Other properties of the source character set are host-specific.
The properties of the execution character set are target-specific. The ARM C and C++
libraries support the ISO 8859-1 (Latin-1 Alphabet) character set with the following
consequences:
• The execution character set is identical to the source character set.
• There are eight bits in a character in the execution character set.
• There are four characters (bytes) in an int. If the memory system is:
Little-endian The bytes are ordered from least significant at the lowest
address to most significant at the highest address.
Big-endian The bytes are ordered from least significant at the highest
address to most significant at the lowest address.
• In C all character constants have type int. In C++ a character constant containing
one character has the type char and a character constant containing more than one
character has the type int. Up to four characters of the constant are represented in
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