Mercurial > hg > octave-nkf > gnulib-hg
changeset 11600:4744bae3ea84
Improve comments.
author | Bruno Haible <bruno@clisp.org> |
---|---|
date | Sun, 31 May 2009 21:46:14 +0200 |
parents | 9ef2eb4b8fe1 |
children | 129bb08ca0ee |
files | ChangeLog lib/alignof.h |
diffstat | 2 files changed, 14 insertions(+), 3 deletions(-) [+] |
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line diff
--- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2009-05-31 Bruno Haible <bruno@clisp.org> + + * lib/alignof.h (alignof_slot, alignof_type, alignof): Document + restriction due to compiler bugs. + Reported by Eric Blake. + 2009-05-31 Simon Josefsson <simon@josefsson.org> Bruno Haible <bruno@clisp.org>
--- a/lib/alignof.h +++ b/lib/alignof.h @@ -21,7 +21,9 @@ #include <stddef.h> /* Determine the alignment of a structure slot (field) of a given type, - at compile time. Note that the result depends on the ABI. */ + at compile time. Note that the result depends on the ABI. + Note: The result cannot be used as a value for an 'enum' constant, + due to bugs in HP-UX 10.20 cc and AIX 3.2.5 xlc. */ #if defined __cplusplus template <class type> struct alignof_helper { char __slot1; type __slot2; }; # define alignof_slot(type) offsetof (alignof_helper<type>, __slot2) @@ -33,7 +35,9 @@ Note that this is not necessarily the same as alignof_slot(type). For example, with GNU C on x86 platforms: alignof_type(double) = 8, but - when -malign-double is not specified: alignof_slot(double) = 4, - - when -malign-double is specified: alignof_slot(double) = 8. */ + - when -malign-double is specified: alignof_slot(double) = 8. + Note: The result cannot be used as a value for an 'enum' constant, + due to bugs in HP-UX 10.20 cc and AIX 3.2.5 xlc. */ #if defined __GNUC__ # define alignof_type __alignof__ #else @@ -42,7 +46,8 @@ /* alignof is an alias for alignof_slot semantics, since that's what most callers need. - Note: The result cannot be used as a value for an 'enum' constant, */ + Note: The result cannot be used as a value for an 'enum' constant, + due to bugs in HP-UX 10.20 cc and AIX 3.2.5 xlc. */ #define alignof alignof_slot #endif /* _ALIGNOF_H */