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variable to avoid invalid constraints in dead code. Use an array of u_char's (inside a struct) instead of a char/short/int/long variable so that the variable and its accesses can be spelled in the same way in all cases and code doesn't need to be cloned just to hold the spelling differences. Fixed strict-aliasing errors in PCPU_SET() and in the amd64 PCPU_GET(). Cast to (void *) as in rev.1.37 of the i386 version where the errors were fixed for the i386 PCPU_GET() only. It would be more correct to copy to and from the temp. variable using memcpy(), but then an ifdef tangle would be required to ensure using the builtin memcpy(). We depend on fairly aggressive optimization to put the temp. variable only in a register despite it being copied using *(type *)(void *)&anothertype and could depend on this when using memcpy() too. This seems to work right even for -O0, but the -O0 case has not been completely tested. This change gives identical object code for all object files in LINT on amd64 (except for one file with a __TIME__ stamp). For LINT on i386 it gives unimportant differences in instruction order and padding in a few object files. This was only tested for -O. This change (actually a previous version of it) gives the following reductions in the number of object files in LINT that fail to compile with -O2 but without the -fno-strict-aliasing kludge: - amd64: 29 (down from 211) - i386: 36 (down from 47) gcc-3.4.6 actually allows the invalid constraints that result from not using the temp. variable, at least with -O[1-2], but gcc-3.3.3 crashes on them and I don't want to depend on compiler bugs.
This is the top level of the FreeBSD source directory. This file was last revised on: $FreeBSD$ For copyright information, please see the file COPYRIGHT in this directory (additional copyright information also exists for some sources in this tree - please see the specific source directories for more information). The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree, the most commonly used one being ``world'', which rebuilds and installs everything in the FreeBSD system from the source tree except the kernel, the kernel-modules and the contents of /etc. The ``world'' target should only be used in cases where the source tree has not changed from the currently running version. See: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/makeworld.html for more information, including setting make(1) variables. The ``buildkernel'' and ``installkernel'' targets build and install the kernel and the modules (see below). Please see the top of the Makefile in this directory for more information on the standard build targets and compile-time flags. Building a kernel is a somewhat more involved process, documentation for which can be found at: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig.html And in the config(8) man page. Note: If you want to build and install the kernel with the ``buildkernel'' and ``installkernel'' targets, you might need to build world before. More information is available in the handbook. The sample kernel configuration files reside in the sys/<arch>/conf sub-directory (assuming that you've installed the kernel sources), the file named GENERIC being the one used to build your initial installation kernel. The file NOTES contains entries and documentation for all possible devices, not just those commonly used. It is the successor of the ancient LINT file, but in contrast to LINT, it is not buildable as a kernel but a pure reference and documentation file. Source Roadmap: --------------- bin System/user commands. contrib Packages contributed by 3rd parties. crypto Cryptography stuff (see crypto/README). etc Template files for /etc. games Amusements. gnu Various commands and libraries under the GNU Public License. Please see gnu/COPYING* for more information. include System include files. kerberos5 Kerberos5 (Heimdal) package. lib System libraries. libexec System daemons. release Release building Makefile & associated tools. rescue Build system for statically linked /rescue utilities. sbin System commands. secure Cryptographic libraries and commands. share Shared resources. sys Kernel sources. tools Utilities for regression testing and miscellaneous tasks. usr.bin User commands. usr.sbin System administration commands. For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see: http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/synching.html