Public Comment Number PC-UK0112 ISO/IEC CD 9899 (SC22N2620) Public Comment =========================================== Date: 1998-02-25 Author: N.M Maclaren Author Affiliation: Self Postal Address: University of Cambridge, Computer Laboratory, New Museums Site, Pembroke Street, Cambridge CB3 3QG, United Kingdom E-mail Address: Telephone Number: +44 1223 334761 Fax Number: +44 1223 334679 Number of individual comments: 1 Comment 1. Category: Feature that should be included Committee Draft subsection: 7.1.6 Title: Symbol providing alignment of objects Detailed description: A somewhat heated debate on the newsgroup comp.std.c brought an interesting omission in C89 to light, which interacts in extremely obscure ways of some the extensions in C9X. It is impossible to write a strictly conforming wrapper for malloc() (e.g. to store the length allocated, use count etc.) because there is no way to discover what the alignment requirement is! So I suggest adding the following to the macros: ALIGN_MAX which expands to an integer constant expression that has type size_t, the value of which is suitable for using as the alignment of any declarable type (i.e. that is a multiple of each value of alignment needed by the processor). The macro shall be suitable for use in #if preprocessing directives. [ The argument for including it here (rather than ) is that it is a property of the compiled code rather than the library, and is needed by freestanding implementations that do their own space management. ]