C Implementation-Defined Behavior; Translation; Environment; Identifiers - Red Hat ENTERPRISE LINUX 4 Manual

A conforming implementation of ISO C is required to document its choice of behavior in each of the
areas that are designated "implementation defined." The following lists all such areas, along with the
section number from the ISO/IEC 9899:1999 standard.

5.1. Translation

[How a diagnostic is identified (3.10, 5.1.1.3).]
•
Diagnostics consist of all the output sent to stderr by GCC.
[Whether each nonempty sequence of white-space characters other than new-line is retained or
•
replaced by one space character in translation phase 3 (5.1.1.2).]

5.2. Environment

The behavior of these points are dependent on the implementation of the C library, and are not defined
by GCC itself.
5.3. Identifiers
[Which additional multibyte characters may appear in identifiers and their correspondence to uni-
•
versal character names (6.4.2).]
[The number of significant initial characters in an identifier (5.2.4.1, 6.4.2).]
•
For internal names, all characters are significant. For external names, the number of significant
characters are defined by the linker; for almost all targets, all characters are significant.

5.4. Characters

[The number of bits in a byte (3.6).]
•
[The values of the members of the execution character set (5.2.1).]
•
[The unique value of the member of the execution character set produced for each of the standard
•
alphabetic escape sequences (5.2.2).]
[The value of a
• char
basic execution character set (6.2.5).]
[Which of
• signed char
"plain" (6.2.5, 6.3.1.1).]
char
[The mapping of members of the source character set (in character constants and string literals) to
•
members of the execution character set (6.4.4.4, 5.1.1.2).]
[The value of an integer character constant containing more than one character or containing a
•
character or escape sequence that does not map to a single-byte execution character (6.4.4.4).]
C Implementation-defined behavior
object into which has been stored any character other than a member of the
or
unsigned char
has the same range, representation, and behavior as
Chapter 5.