HardenedBSD/share/mk/bsd.README
Alex Richardson 7bc797e3f3 Add build system support for ASAN+UBSAN instrumentation
This adds two new options WITH_ASAN/WITH_UBSAN that can be set to
enable instrumentation of all binaries with AddressSanitizer and/or
UndefinedBehaviourSanitizer. This current patch is almost sufficient
to get a complete buildworld with sanitizer instrumentation but in
order to actually build and boot a system it depends on a few more
follow-up commits.

Reviewed By:	brooks, kib, markj
Differential Revision: https://reviews.freebsd.org/D31043
2021-08-02 14:33:24 +01:00

747 lines
24 KiB
Plaintext

# @(#)bsd.README 8.2 (Berkeley) 4/2/94
# $FreeBSD$
This is the README file for the "include" files for the FreeBSD
source tree. The files are installed in /usr/share/mk, and are by
convention, named with the suffix ".mk". These files store several
build options and should be handled with caution.
Note, this file is not intended to replace reading through the .mk
files for anything tricky.
There are two main types of make include files. One type is the generally
usable make include files, such as bsd.prog.mk and bsd.lib.mk. The other is
the internal make include files, such as bsd.files.mk and bsd.man.mk, which
can not/should not be used directly but are used by the other make include
files. In most cases it is only interesting to include bsd.prog.mk or
bsd.lib.mk.
bsd.arch.inc.mk - includes arch-specific Makefile.$arch
bsd.compat.mk - definitions for building programs against compat ABIs
bsd.compiler.mk - defined based on current compiler
bsd.confs.mk - install of configuration files
bsd.cpu.mk - sets CPU/arch-related variables (included from sys.mk)
bsd.crunchgen.mk - building crunched binaries using crunchgen(1)
bsd.dep.mk - handle Makefile dependencies
bsd.dirs.mk - handle directory creation
bsd.doc.mk - building troff system documents
bsd.endian.mk - TARGET_ENDIAN=1234(little) or 4321 (big) for target
bsd.files.mk - install of general purpose files
bsd.incs.mk - install of include files
bsd.info.mk - building GNU Info hypertext system (deprecated)
bsd.init.mk - initialization for the make include files
bsd.kmod.mk - building loadable kernel modules
bsd.lib.mk - support for building libraries
bsd.libnames.mk - define library names
bsd.links.mk - install of links (sym/hard)
bsd.man.mk - install of manual pages and their links
bsd.nls.mk - build and install of NLS catalogs
bsd.obj.mk - creating 'obj' directories and cleaning up
bsd.own.mk - define common variables
bsd.port.mk - building ports
bsd.port.post.mk - building ports
bsd.port.pre.mk - building ports
bsd.port.subdir.mk - targets for building subdirectories for ports
bsd.prog.mk - building programs from source files
bsd.progs.mk - build multiple programs from sources
bsd.snmpmod.mk - building modules for the SNMP daemon bsnmpd
bsd.subdir.mk - targets for building subdirectories
bsd.sys.mk - common settings used for building FreeBSD sources
bsd.test.mk - building test programs from source files
sys.mk - default rules for all makes
This file does not document bsd.port*.mk. They are documented in ports(7).
See also make(1), mkdep(1), style.Makefile(5) and `PMake - A
Tutorial', located in /usr/share/doc/psd/12.make.
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Random things worth knowing about this document:
If appropriate when documenting the variables the default value is
indicated using square brackets e.g. [gzip].
In some cases the default value depend on other values (e.g. system
architecture). In these cases the most common value is indicated.
This document contains some simple examples of the usage of the BSD make
include files. For more examples look at the makefiles in the FreeBSD
source tree.
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RANDOM THINGS WORTH KNOWING:
The files are like C-style #include files, and pretty much behave like
you'd expect. The syntax is slightly different in that a single '.' is
used instead of the hash mark, i.e. ".include <bsd.prog.mk>".
One difference that will save you lots of debugging time is that inclusion
of the file is normally done at the *end* of the Makefile. The reason for
this is because .mk files often modify variables and behavior based on the
values of variables set in the Makefile. To make this work, remember that
the FIRST target found is the target that is used, i.e. if the Makefile has:
a:
echo a
a:
echo a number two
the command "make a" will echo "a". To make things confusing, the SECOND
variable assignment is the overriding one, i.e. if the Makefile has:
a= foo
a= bar
b:
echo ${a}
the command "make b" will echo "bar". This is for compatibility with the
way the V7 make behaved.
It's fairly difficult to make the BSD .mk files work when you're building
multiple programs in a single directory. It's a lot easier to split up
the programs than to deal with the problem. Most of the agony comes from
making the "obj" directory stuff work right, not because we switch to a new
version of make. So, don't get mad at us, figure out a better way to handle
multiple architectures so we can quit using the symbolic link stuff.
(Imake doesn't count.)
The file .depend in the source directory is expected to contain dependencies
for the source files. This file is read automatically by make after reading
the Makefile.
The variable DESTDIR works as before. It's not set anywhere but will change
the tree where the file gets installed.
The profiled libraries are no longer built in a different directory than
the regular libraries. A new suffix, ".po", is used to denote a profiled
object, and ".pico" denotes a position-independent relocatable object.
".nossppico" denotes a position-independent relocatable object without
stack smashing protection and without sanitizer instrumentation.
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The following variables are common:
AFLAGS.${SRC}
Flags dependent on source file name.
AFLAGS.${TARGET}
Flags dependent on output file name.
ACFLAGS.${SRC}
Flags dependent on source file name.
ACFLAGS.${TARGET}
Flags dependent on output file name.
CFLAGS.${SRC}
Flags dependent on source file name.
CFLAGS.${TARGET}
Flags dependent on output file name.
CFLAGS.${COMPILER_TYPE}
Flags dependent on compiler added to CFLAGS.
CFLAGS.${MACHINE_ARCH}
Architectural flags added to CFLAGS.
CFLAGS_NO_SIMD Add this to CFLAGS for programs that don't want any SIMD
instructions generated. It is setup in bsd.cpu.mk to an
appropriate value for the compiler and target.
CXXFLAGS.${COMPILER_TYPE}
Flags dependent on compiler added to CXXFLAGS.
CXXFLAGS.${MACHINE_ARCH}
Architectural flags added to CXXFLAGS.
CXXFLAGS.${SRC}
Flags dependent on source file name.
CXXFLAGS.${TARGET}
Flags dependent on output file name.
COMPILER_FEATURES
A list of features that the compiler supports. Zero or
more of:
c++11 Supports full C++ 11 standard.
COMPILER_TYPE Type of compiler, either clang or gcc, though other
values are possible. Don't assume != clang == gcc.
COMPILER_VERSION
A numeric constant equal to:
major * 10000 + minor * 100 + tiny
for the compiler's self-reported version.
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The include file <sys.mk> has the default rules for all makes, in the BSD
environment or otherwise. You probably don't want to touch this file.
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The include file <bsd.arch.inc.mk> includes other Makefiles for specific
architectures, if they exist. It will include the first of the following
files that it finds: Makefile.${MACHINE}, Makefile.${MACHINE_ARCH},
Makefile.${MACHINE_CPUARCH}
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The include file <bsd.man.mk> handles installing manual pages and their
links.
It has three targets:
all-man:
build manual pages.
maninstall:
install the manual pages and their links.
manlint:
verify the validity of manual pages.
It sets/uses the following variables:
MAN The manual pages to be installed (use a .1 - .9 suffix).
MANDIR Base path for manual installation.
MANGRP Manual group.
MANMODE Manual mode.
MANOWN Manual owner.
MANSUBDIR Subdirectory under the manual page section, i.e. "/vax"
or "/tahoe" for machine specific manual pages.
MLINKS List of manual page links (using a .1 - .9 suffix). The
linked-to file must come first, the linked file second,
and there may be multiple pairs. The files are hard-linked.
The include file <bsd.man.mk> includes a file named "../Makefile.inc" if
it exists.
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The include file <bsd.own.mk> contains the owners, groups, etc. for both
manual pages and binaries.
It has no targets.
It sets/uses the following variables:
BINGRP Binary group.
BINMODE Binary mode.
BINOWN Binary owner.
MANDIR Base path for manual installation.
MANGRP Manual group.
MANMODE Manual mode.
MANOWN Manual owner.
INSTALL_LINK Command to install a hard link.
INSTALL_SYMLINK Command to install a symbolic link.
INSTALL_RSYMLINK Command to install a relative symbolic link.
LINKOWN Owner of hard links created by INSTALL_LINK.
LINKGRP Group of hard links created by INSTALL_LINK.
LINKMODE Mode of hard links created by INSTALL_LINK.
SYMLINKOWN Owner of hard links created by INSTALL_[R]SYMLINK.
SYMLINKGRP Group of hard links created by INSTALL_[R]SYMLINK.
SYMLINKMODE Mode of hard links created by INSTALL_[R]SYMLINK.
This file is generally useful when building your own Makefiles so that
they use the same default owners etc. as the rest of the tree.
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The include file <bsd.prog.mk> handles building programs from one or
more source files, along with their manual pages. It has a limited number
of suffixes, consistent with the current needs of the BSD tree.
It has seven targets:
all:
build the program and its manual page
clean:
remove the program and any object files.
cleandir:
remove all of the files removed by the target clean, as
well as .depend, tags, and any manual pages.
depend:
make the dependencies for the source files, and store
them in the file .depend.
install:
install the program and its manual pages; if the Makefile
does not itself define the target install, the targets
beforeinstall and afterinstall may also be used to cause
actions immediately before and after the install target
is executed.
tags:
create a tags file for the source files.
It sets/uses the following variables:
ACFLAGS Flags to the compiler when preprocessing and
assembling .S files.
AFLAGS Flags to the assembler when assembling .s files.
BINGRP Binary group.
BINMODE Binary mode.
BINOWN Binary owner.
CFLAGS Flags to the compiler when creating C objects.
CLEANDIRS Additional files (CLEANFILES) and directories (CLEANDIRS) to
CLEANFILES remove during clean and cleandir targets. "rm -rf" and
"rm -f" are used, respectively.
DIRS A list of variables referring to directories. For example:
DIRS+= FOO
FOO= /usr/share/foo
Owner, Group, Mode and Flags are handled by FOO_OWN,
FOO_GRP, FOO_MODE and FOO_FLAGS, respectively.
This allows FILESDIR to be set to FOO, and the directory
will be created before the files are installed and the
dependencies will be set correctly.
DPADD Additional dependencies for the program. Usually used for
libraries. For example, to depend on the compatibility and
utility libraries use:
DPADD=${LIBCOMPAT} ${LIBUTIL}
There is a predefined identifier for each (non-profiled,
non-shared) library and object. Library file names are
transformed to identifiers by removing the extension and
converting to upper case.
There are no special identifiers for profiled or shared
libraries or objects. The identifiers for the standard
libraries are used in DPADD. This works correctly iff all
the libraries are built at the same time. Unfortunately,
it causes unnecessary relinks to shared libraries when
only the static libraries have changed. Dependencies on
shared libraries should be only on the library version
numbers.
FILES A list of non-executable files.
The installation is controlled by the FILESNAME, FILESOWN,
FILESGRP, FILESMODE, FILESDIR variables that can be
further specialized by FILES<VAR>_<file>.
LDADD Additional loader objects. Usually used for libraries.
For example, to load with the compatibility and utility
libraries, use:
LDADD=-lutil -lcompat
LDADD.${TAREGT}
Loader objects dependent on output file name.
LDFLAGS Additional loader flags. Passed to the loader via CC,
since that's used to link programs as well, so loader
specific flags need to be prefixed with -Wl, to work.
LDFLAGS.${TARGET}
Flags dependent on output file name.
LIBADD Additional libraries. This is for base system libraries
and is only valid inside of the /usr/src tree.
Use LIBADD=name instead of LDADD=-lname.
LIBADD.${TARGET}
Libraries dependent on output file name.
LINKS The list of binary links; should be full pathnames, the
linked-to file coming first, followed by the linked
file. The files are hard-linked. For example, to link
/bin/test and /bin/[, use:
LINKS= /bin/test /bin/[
LINKOWN Owner of links created with LINKS [${BINOWN}].
LINKGRP Group of links created with LINKS [${BINGRP}].
LINKMODE Mode of links created with LINKS [${BINMODE}].
MAN Manual pages. If no MAN variable is defined,
"MAN=${PROG}.1" is assumed. See bsd.man.mk for more details.
PROG The name of the program to build. If not supplied, nothing
is built.
PROGNAME The name that the above program will be installed as, if
different from ${PROG}.
PROG_CXX If defined, the name of the program to build. Also
causes <bsd.prog.mk> to link the program with the
standard C++ library. PROG_CXX overrides the value
of PROG if PROG is also set.
PROGS When used with <bsd.progs.mk>, allow building multiple
PROGS_CXX PROG and PROG_CXX in one Makefile. To define
individual variables for each program the VAR.prog
syntax should be used. For example:
PROGS= foo bar
SRCS.foo= foo_src.c
LDADD.foo= -lutil
SRCS.bar= bar_src.c
The supported variables are:
- BINDIR
- BINGRP
- BINMODE
- BINOWN
- CFLAGS
- CXXFLAGS
- DEBUG_FLAGS
- DPADD
- DPSRCS
- INTERNALPROG (no installation)
- LDADD
- LDFLAGS
- LIBADD
- LINKS
- MAN
- MLINKS
- MK_WERROR=no
- PROGNAME
- SRCS
- STRIP
- WARNS
SCRIPTS A list of interpreter scripts [file.{sh,csh,pl,awk,...}].
The installation is controlled by the SCRIPTSNAME, SCRIPTSOWN,
SCRIPTSGRP, SCRIPTSMODE, SCRIPTSDIR variables that can be
further specialized by SCRIPTS<VAR>_<script>.
SRCS List of source files to build the program. If SRCS is not
defined, it's assumed to be ${PROG}.c or, if PROG_CXX is
defined, ${PROG_CXX}.cc.
STRIP The flag passed to the install program to cause the binary
to be stripped. This is to be used when building your
own install script so that the entire system can be made
stripped/not-stripped using a single nob.
SUBDIR A list of subdirectories that should be built as well.
Each of the targets will execute the same target in the
subdirectories.
The include file <bsd.prog.mk> includes the file named "../Makefile.inc"
if it exists, as well as the include file <bsd.man.mk>.
Some simple examples:
To build foo from foo.c with a manual page foo.1, use:
PROG= foo
.include <bsd.prog.mk>
To build foo from foo.c with a manual page foo.2, add the line:
MAN= foo.2
If foo does not have a manual page at all, add the line:
MAN=
If foo has multiple source files, add the line:
SRCS= a.c b.c c.c d.c
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The include file, <bsd.compat.mk>, allows programs (built with
<bsd.prog.mk>) to be built for one the ABI(s) supported by the
top-level Makefile.libcompat. It requires that <bsd.prog.mk> also be
included.
NEED_COMPAT Build and link targeting a compatibility ABI or fail if it
is not available. Supported values are "32", "soft", and
"any" being a wildcard.
WANT_COMPAT Similar to NEED_COMPAT, but build with the base ABI if
the specified ABI is not available.
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The include file, <bsd.snmpmod.mk>, handles building MIB modules for bsnmpd
from one or more source files, along with their manual pages. It has a
limited number of suffixes, consistent with the current needs of the BSD
tree.
bsd.snmpmod.mk leverages bsd.lib.mk for building MIB modules and
bsd.files.mk for installing MIB description and definition files.
It implements the following additional targets:
smilint:
execute smilint on the MIBs defined by BMIBS.
The net-mgmt/libsmi package must be installed before
executing this target. The net-mgmt/net-snmp package
should be installed as well to reduce false positives
from smilint.
It sets/uses the following variables:
BMIBS The MIB definitions to install.
BMIBSDIR The directory where the MIB definitions are installed.
This defaults to `${SHAREDIR}/snmp/mibs`.
DEFS The MIB description files to install.
DEFSDIR The directory where MIB description files are installed.
This defaults to `${SHAREDIR}/snmp/defs`.
EXTRAMIBDEFS Extra MIB description files to use as input when
generating ${MOD}_oid.h and ${MOD}_tree.[ch].
EXTRAMIBSYMS Extra MIB definition files used only for extracting
symbols.
EXTRAMIBSYMS are useful when resolving inter-module
dependencies and are useful with files containing only
enum-definitions.
See ${MOD}_oid.h for more details.
LOCALBASE The package root where smilint and the net-snmp
definitions can be found
MOD The bsnmpd module name.
SMILINT smilint binary to use with the smilint make target.
SMILINT_FLAGS flags to pass to smilint.
SMIPATH A colon-separated directory path where MIBs definitions
can be found. See "SMIPATH" in smi_config for more
details.
XSYM MIB names to extract symbols for. See ${MOD}_oid.h for
more details.
It generates the following files:
${MOD}_tree.c A source file and header which programmatically describes
${MOD}_tree.h the MIB (type, OID name, ACCESS attributes, etc).
The files are generated via "gensnmptree -p".
See gensnmptree(1) for more details.
${MOD}_oid.h A header which programmatically describes the MIB root and
MIB tables.
The files are generated via "gensnmptree -e".
See gensnmptree(1) for more details.
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The include file <bsd.subdir.mk> contains the default targets for building
subdirectories. It has the same seven targets as <bsd.prog.mk>: all, clean,
cleandir, depend, install, and tags. For all of the directories listed in the
variable SUBDIRS, the specified directory will be visited and the target made.
There is also a default target which allows the command "make subdir" where
subdir is any directory listed in the variable SUBDIRS.
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The include file <bsd.lib.mk> has support for building libraries. It has the
same seven targets as <bsd.prog.mk>: all, clean, cleandir, depend, install, and
tags. It has a limited number of suffixes, consistent with the current needs of
the BSD tree.
It sets/uses the following variables:
LDADD Additional loader objects.
LIB The name of the library to build. Both a shared and static
library will be built. NO_PIC can be set to only build a
static library.
LIBADD Additional libraries. This is for base system libraries
and is only valid inside of the /usr/src tree.
Use LIBADD=name instead of LDADD=-lname.
LIBDIR Target directory for libraries.
LIBGRP Library group.
LIBMODE Library mode.
LIBOWN Library owner.
LIBRARIES_ONLY Do not build or install files other than the library.
LIB_CXX The name of the library to build. It also causes
<bsd.lib.mk> to link the library with the
standard C++ library. LIB_CXX overrides the value
of LIB if LIB is also set. Both a shared and static library
will be built. NO_PIC can be set to only build a static
library.
LINKS The list of binary links; should be full pathnames, the
linked-to file coming first, followed by the linked
file. The files are hard-linked. For example, to link
/bin/test and /bin/[, use:
LINKS= /bin/test /bin/[
LINKOWN Owner of links created with LINKS [${LIBOWN}].
LINKGRP Group of links created with LINKS [${LIBGRP}].
LINKMODE Mode of links created with LINKS [${LIBMODE}].
LINTLIBDIR Target directory for lint libraries.
MAN The manual pages to be installed. See bsd.man.mk for more
details.
SHLIB Like LIB but only builds a shared library.
SHLIB_CXX Like LIB_CXX but only builds a shared library.
SHLIB_LDSCRIPT Template file to generate shared library linker script.
If not defined, a simple symlink is created to the real
shared object.
SRCS List of source files to build the library. Suffix types
.s, .c, and .f are supported. Note, .s files are preferred
to .c files of the same name. (This is not the default for
versions of make.)
The include file <bsd.lib.mk> includes the file named "../Makefile.inc"
if it exists, as well as the include file <bsd.man.mk>.
It has rules for building profiled objects; profiled libraries are
built by default.
Libraries are ranlib'd before installation.
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The include file <bsd.test.mk> handles building one or more test programs
intended to be used in the FreeBSD Test Suite under /usr/tests/.
It has seven targets:
all:
build the test programs.
check:
runs the test programs with kyua test.
The beforecheck and aftercheck targets will be invoked, if
defined, to execute commands before and after the realcheck
target has been executed, respectively.
The devel/kyua package must be installed before invoking this
target.
clean:
remove the test programs and any object files.
cleandir:
remove all of the files removed by the target clean, as
well as .depend and tags.
depend:
make the dependencies for the source files, and store
them in the file .depend.
install:
install the test programs and their data files; if the
Makefile does not itself define the target install, the
targets beforeinstall and afterinstall may also be used
to cause actions immediately before and after the
install target is executed.
tags:
create a tags file for the source files.
It sets/uses the following variables, among many others:
ATF_TESTS_C The names of the ATF C test programs to build.
ATF_TESTS_CXX The names of the ATF C++ test programs to build.
ATF_TESTS_SH The names of the ATF sh test programs to build.
GTESTS The names of the GoogleTest test programs to build.
KYUAFILE If 'auto' (the default), generate a Kyuafile out of the
test programs defined in the Makefile. If 'yes', then a
manually-crafted Kyuafile must be supplied with the
sources. If 'no', no Kyuafile is installed (useful for
subdirectories providing helper programs or data files
only).
LOCALBASE The --prefix for the kyua package.
The value of LOCALBASE defaults to /usr/local .
NOT_FOR_TEST_SUITE
If defined, none of the built test programs get
installed under /usr/tests/ and no Kyuafile is
automatically generated. Should not be used within the
FreeBSD source tree but is provided for the benefit of
third-parties.
PLAIN_TESTS_C The names of the plain (legacy) programs to build.
PLAIN_TESTS_CXX The names of the plain (legacy) test programs to build.
PLAIN_TESTS_SH The names of the plain (legacy) test programs to build.
TAP_PERL_INTERPRETER
Path to the Perl interpreter to be used for
TAP-compliant test programs that are written in Perl.
Refer to TAP_TESTS_PERL for details.
TAP_TESTS_C The names of the TAP-compliant C test programs to build.
TAP_TESTS_CXX The names of the TAP-compliant C++ test programs to
build.
TAP_TESTS_PERL The names of the TAP-compliant Perl test programs to
build. The corresponding source files should end with
the .pl extension; the test program is marked as
requiring Perl; and TAP_PERL_INTERPRETER is used in the
built scripts as the interpreter of choice.
TAP_TESTS_SH The names of the TAP-compliant sh test programs to
build.
TESTSBASE Installation prefix for tests. Defaults to /usr/tests
TESTSDIR Path to the installed tests. Must be a subdirectory of
TESTSBASE and the subpath should match the relative
location of the tests within the src tree.
The value of TESTSDIR defaults to
${TESTSBASE}/${RELDIR:H} , e.g. /usr/tests/bin/ls when
included from bin/ls/tests .
TESTS_SUBDIRS List of subdirectories containing tests into which to
recurse. Differs from SUBDIR in that these directories
get registered into the automatically-generated
Kyuafile (if any).
The actual building of the test programs is performed by <bsd.prog.mk>.
Please see the documentation above for this other file for additional
details on the behavior of <bsd.test.mk>.