[Bug middle-end/36757] New: __builtin_signbit should be type-generic

["jsm28 at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

The function __builtin_signbit should be type-generic so that libraries can
define the standard signbit macro with
"#define signbit(x) __builtin_signbit(x)".

(Mentioned several times before in the context of discussions of the other
type-generic built-in functions, but doesn't seem to be filed in Bugzilla
at present.)

It's necessary to avoid the type-generic signbit expanding to call a library
function that may not exist, but as all currently supported floating-point
formats do have a sign bit specified in signbit_ro I believe the case
of failing to expand inline can be made into an abort.


-- 
           Summary: __builtin_signbit should be type-generic
           Product: gcc
           Version: 4.4.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jsm28 at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36757