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Language Extensions
static int y = c + 10; /* error ext */
static int const z = c + 10; /* error ext */
extern int *const cp = (int*)0x100; /* ok ok */
extern int *const xp = cp + 0x100; /* error ext */
static int * yp = cp + 0x100; /* error ext */
static int *const zp = cp + 0x100; /* error ext */
This indicates the behavior defined by the ISO C Standard, Std, and the behavior in
RVCT:
• ok indicates that the statement is accepted in all C modes.
• ext is an extension to the ISO C Standard. The behavior depends on the strict
mode used when compiling C:
Non strict
Accepted, without a warning.
--strict_warnings
Accepted, but gives a warning.
--strict
Conforms to the ISO C Standard, but gives an error.
See also
• --extended_initializers, --no_extended_initializers on page 2-56
• --strict, --no_strict on page 2-119
• --strict_warnings on page 2-120.
3.4.2 Array and pointer extensions
The following array and pointer extensions are supported:
• Assignment and pointer differences are permitted between pointers to types that
are interchangeable but not identical, for example, unsigned char * and char *.
This includes pointers to same-sized integral types, typically, int * and long *. A
warning is issued.
Assignment of a string constant to a pointer to any kind of character is permitted
without a warning.
• Assignment of pointer types is permitted in cases where the destination type has
added type qualifiers that are not at the top level, for example, assigning int ** to
const int **. Comparisons and pointer difference of such pairs of pointer types
are also permitted. A warning is issued.
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