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Revision 1.4, Fri Jun 6 05:51:46 2008 UTC (12 years, 4 months ago) by yamt
fix a typo
.\" $NetBSD: __builtin_object_size.3,v 1.4 2008/06/06 05:51:46 yamt Exp $ .\" .\" Copyright (c) 2007 The NetBSD Foundation, Inc. .\" All rights reserved. .\" .\" This code is derived from software contributed to The NetBSD Foundation .\" by Christos Zoulas. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS .\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED .\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR .\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS .\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .\" .Dd May 23, 2007 .Dt __BUILTIN_OBJECT_SIZE 3 .Os .Sh NAME .Nm __builtin_object_size .Nd return the size of the given object .Sh LIBRARY .Ft size_t .Fn __builtin_object_size "void *ptr" "int type" .Sh DESCRIPTION The .Fn __builtin_object_size function is a .Xr gcc 1 built-in function that returns the size of the .Fa ptr object if known at compile time and the object does not have any side effects. .Sh RETURN VALUES If the size of the object is not known or it has side effects the .Fn __builtin_object_size function returns: .Bl -tag -width (size_t)-1 .It Dv (size_t)-1 for .Fa type .Dv 0 and .Dv 1 . .It Dv (size_t)0 for .Fa type .Dv 2 and .Dv 3 . .El .Pp If the size of the object is known, then the .Fn __builtin_object_size function returns the maximum size of all the objects that the compiler knows that they can be pointed to by .Fa ptr when .Fa type .Dv \*[Am] 2 == 0 , and the minimum size when .Fa type .Dv \*[Am] 2 != 0 . .Sh SEE ALSO .Xr gcc 1 , .Xr ssp 3 .Sh HISTORY The .Fn __builtin_object_size appeared in gcc 4.1.