diff options
Diffstat (limited to 'nuttx/include/stddef.h')
| -rw-r--r-- | nuttx/include/stddef.h | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/nuttx/include/stddef.h b/nuttx/include/stddef.h index dd8385c9f..6e24fbd7c 100644 --- a/nuttx/include/stddef.h +++ b/nuttx/include/stddef.h @@ -48,16 +48,20 @@ /* The <stddef.h> header shall define the following macros: * * NULL - * The Null pointer constant. + * The null pointer constant. * - * NOTE: Currently the definition of NULL is in sys/types.h but should be - * moved here sometime. + * NOTE: Currently the definition of NULL is in sys/types.h but should + * be moved here sometime. * * offsetof(type, member-designator) * Integer constant expression of type size_t, the value of which is the * offset in bytes to the structure member (member-designator), from the * beginning of its structure (type). * + * NOTE: This version of offsetof() depends on behaviors that could be + * undefined for some compilers. It would be better to use a builtin + * function if one exists. + * * Reference: Opengroup.org */ @@ -71,6 +75,9 @@ * ptrdiff_t * Signed integer type of the result of subtracting two pointers. * + * NOTE: This type assumes that ssize_t will cover the largest address + * difference. This might not be true of CONFIG_MM_SMALL is defined. + * * wchar_t * Integer type whose range of values can represent distinct wide-character * codes for all members of the largest character set specified among the @@ -82,8 +89,8 @@ * size_t * Unsigned integer type of the result of the sizeof operator. * - * NOTE: Currently the type definitions of both wchar_t and size_t are in - * sys/types.h but should be moved here sometime. + * NOTE: Currently the type definitions of both wchar_t and size_t are + * in sys/types.h but should be moved here sometime. * * The implementation shall support one or more programming environments in * which the widths of ptrdiff_t, size_t, and wchar_t are no greater than the |