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    SubjectRe: x32 and width of blksize_t, suseconds_t
    On Fri, 16 Mar 2012, H. Peter Anvin wrote:

    > On 03/16/2012 01:19 AM, Paul Eggert wrote:
    > > Come to think of it, the proposed x32 patch may have issues
    > > with blksize_t and suseconds_t as well. POSIX says that an x32
    > > implementation must support at least one programming environment
    > > (presumably settable via a feature test macro) where blksize_t
    > > and suseconds_t are no wider than 'long'; see
    > > <>.
    > > But if I understand things correctly, x32 glibc would
    > > define these to be 'long long'. This issue affects system
    > > calls such as 'stat' and 'select'.
    > That's just not going to happen, sorry. Why on Earth is this a
    > requirement? It makes no sense whatsoever.

    It's probably to support code written for C90. Note that it's the
    POSIX-conforming system as a whole that is to support such an environment
    - but it might be an environment that uses the traditional 32-bit or
    64-bit ABIs, it needn't be one using the x32 ABI. "getconf
    POSIX_V7_WIDTH_RESTRICTED_ENVS" must print the names of the environments
    meeting this requirement; if one is "POSIX_V7_ILP32_OFF32", for example,
    then "getconf POSIX_V7_ILP32_OFF32_CFLAGS" will print the flags (maybe
    -m32) and likewise for _LDFLAGS and _LIBS. In glibc this means defining
    appropriate macros in bits/environment.h to give the right flags - and
    also probably changing posix/confstr.c which has comments saying
    "Currently this means all environment which the system allows." (the x32
    patch series may need to adjust this in some way).

    Joseph S. Myers

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