| 1. | Physical source file characters are mapped, in an
implementation-defined manner,
to the basic source character set (introducing new-line characters for end-of-line
indicators) if necessary. The set of physical source file characters accepted is implementation-defined. Any
source file character not in the
basic source character set
is replaced by the
universal-character-name that
designates that character. An implementation may use any internal
encoding, so long as an actual extended character encountered in the
source file, and the same extended character expressed in the source
file as a universal-character-name (e.g., using the \uXXXX notation), are handled equivalently
except where this replacement is reverted ([lex.pptoken]) in a raw string literal. |
| 2. | Each instance of a backslash character (\)
immediately followed by a new-line character is deleted, splicing
physical source lines to form logical source lines. Only the last
backslash on any physical source line shall be eligible for being part
of such a splice. Except for splices reverted in a raw string literal, if a splice results in
a character sequence that matches the
syntax of a universal-character-name, the behavior is
undefined. A source file that is not empty and that does not end in a new-line
character, or that ends in a new-line character immediately preceded by a
backslash character before any such splicing takes place,
shall be processed as if an additional new-line character were appended
to the file. |
| 3. | The source file is decomposed into preprocessing
tokens ([lex.pptoken]) and sequences of whitespace characters
(including comments).
Each comment is replaced by one space character. New-line characters are
retained. Whether each nonempty sequence of whitespace characters other
than new-line is retained or replaced by one space character is
unspecified. The process of dividing a source file's
characters into preprocessing tokens is context-dependent. |
| 4. | Preprocessing directives are executed, macro invocations are
expanded, and _Pragma unary operator expressions are executed. If a character sequence that matches the syntax of a
universal-character-name is produced by token
concatenation, the behavior is undefined. A
#include preprocessing directive causes the named header or
source file to be processed from phase 1 through phase 4, recursively. All preprocessing directives are then deleted. |
| 5. | Each
basic-c-char,
basic-s-char, and
r-char
in a character-literal or a string-literal,
as well as each
escape-sequence and universal-character-name
in a character-literal or a non-raw string literal,
is encoded in the literal's associated character encoding as specified in
[lex.ccon] and [lex.string]. |
| 6. | Adjacent string-literals are concatenated
and a null character is appended to the result
as specified in [lex.string]. |
| 7. | Whitespace characters separating tokens are no longer
significant. Each preprocessing token is converted into a
token ([lex.token]). The resulting tokens are syntactically and
semantically analyzed and translated as a translation unit. [Note 1: The process of analyzing and translating the tokens can occasionally
result in one token being replaced by a sequence of other
tokens ([temp.names]). — end note]
It is
implementation-defined
whether the sources for
module units and header units
on which the current translation unit has an interface
dependency ([module.unit], [module.import])
are required to be available. [Note 2: Source files, translation
units and translated translation units need not necessarily be stored as
files, nor need there be any one-to-one correspondence between these
entities and any external representation. The description is conceptual
only, and does not specify any particular implementation. — end note] |
| 8. | Translated translation units and instantiation units are combined
as follows:
Each translated translation unit is examined to
produce a list of required instantiations. [Note 4: This can include
instantiations which have been explicitly
requested ([temp.explicit]). — end note]
The definitions of the
required templates are located. It is implementation-defined whether the
source of the translation units containing these definitions is required
to be available.
All the required instantiations
are performed to produce
instantiation units.
The
program is ill-formed if any instantiation fails. |
| 9. |