The number of bits in a byte (C90 3.4, C99 and C11 3.6).
Determined by ABI.
C99 and C11 5.2.1).
Determined by ABI.
for each of the standard alphabetic escape sequences (C90, C99 and C11 5.2.2).
Determined by ABI.
character other than a member of the basic execution character set (C90 6.1.2.5, C99 and C11 6.2.5).
Determined by ABI.
range, representation, and behavior as plain char (C90 6.1.2.5, C90 6.2.1.1, C99 and C11 6.2.5, C99 and C11 6.3.1.1).
Determined by ABI. The options -funsigned-char and -fsigned-char change the default. C Dialect OptionsOptions Controlling C Dialect.
constants and string literals) to members of the execution character set (C90 6.1.3.4, C99 and C11 6.4.4.4, C90, C99 and C11 5.1.1.2).
Determined by ABI.
character or containing a character or escape sequence that does not map to a single-byte execution character (C90 6.1.3.4, C99 and C11 6.4.4.4).
Implementation-defined behaviorImplementation-defined behaviorcppThe C Preprocessor.
multibyte character or a single multibyte character that maps to multiple members of the extended execution character set, or containing a multibyte character or escape sequence not represented in the extended execution character set (C90 6.1.3.4, C99 and C11 6.4.4.4).
Implementation-defined behaviorImplementation-defined behaviorcppThe C Preprocessor.
of a single multibyte character that maps to a member of the extended execution character set into a corresponding wide character code (C90 6.1.3.4, C99 and C11 6.4.4.4).
Implementation-defined behaviorImplementation-defined behaviorcppThe C Preprocessor.
concatenated and, if so, the treatment of the resulting multibyte character sequence (C11 6.4.5).
Such tokens may not be concatenated.
corresponding wide character codes (C90 6.1.4, C99 and C11 6.4.5).
Implementation-defined behaviorImplementation-defined behaviorcppThe C Preprocessor.
sequence not represented in the execution character set (C90 6.1.4, C99 and C11 6.4.5).
Implementation-defined behaviorImplementation-defined behaviorcppThe C Preprocessor.
char32_t where the corresponding standard encoding macro (__STDC_ISO_10646__, __STDC_UTF_16__, or __STDC_UTF_32__) is not defined (C11 6.10.8.2).
Implementation-defined behaviorImplementation-defined behaviorcppThe C Preprocessor. char16_t and char32_t literals are always encoded in UTF-16 and UTF-32 respectively.