freebsd-dev/share/mk/bsd.opts.mk
Ed Maste bcf99d2d99 Add WITH_PIE knob to build Position Independent Executables
Building binaries as PIE allows the executable itself to be loaded at a
random address when ASLR is enabled (not just its shared libraries).

With this change PIE objects have a .pieo extension and INTERNALLIB
libraries libXXX_pie.a.

MK_PIE is disabled for some kerberos5 tools, Clang, and Subversion, as
they explicitly reference .a libraries in their Makefiles.  These can
be addressed on an individual basis later.  MK_PIE is also disabled for
rtld-elf because it is already position-independent using bespoke
Makefile rules.

Currently only dynamically linked binaries will be built as PIE.

Discussed with:	dim
Reviewed by:	kib
MFC after:	1 month
Relnotes:	Yes
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D18423
2019-02-15 22:22:38 +00:00

113 lines
3.0 KiB
Makefile

# $FreeBSD$
#
# Option file for src builds.
#
# Users define WITH_FOO and WITHOUT_FOO on the command line or in /etc/src.conf
# and /etc/make.conf files. These translate in the build system to MK_FOO={yes,no}
# with (usually) sensible defaults.
#
# Makefiles must include bsd.opts.mk after defining specific MK_FOO options that
# are applicable for that Makefile (typically there are none, but sometimes there
# are exceptions). Recursive makes usually add MK_FOO=no for options that they wish
# to omit from that make.
#
# Makefiles must include bsd.mkopt.mk before they test the value of any MK_FOO
# variable.
#
# Makefiles may also assume that this file is included by bsd.own.mk should it
# need variables defined there prior to the end of the Makefile where
# bsd.{subdir,lib.bin}.mk is traditionally included.
#
# The old-style YES_FOO and NO_FOO are being phased out. No new instances of them
# should be added. Old instances should be removed since they were just to
# bridge the gap between FreeBSD 4 and FreeBSD 5.
#
# Makefiles should never test WITH_FOO or WITHOUT_FOO directly (although an
# exception is made for _WITHOUT_SRCONF which turns off this mechanism
# completely).
#
.if !target(__<bsd.opts.mk>__)
__<bsd.opts.mk>__:
.if !defined(_WITHOUT_SRCCONF)
#
# Define MK_* variables (which are either "yes" or "no") for users
# to set via WITH_*/WITHOUT_* in /etc/src.conf and override in the
# make(1) environment.
# These should be tested with `== "no"' or `!= "no"' in makefiles.
# The NO_* variables should only be set by makefiles for variables
# that haven't been converted over.
#
# Only these options are used by bsd.*.mk. KERBEROS and OPENSSH are
# unfortunately needed to support statically linking the entire
# tree. su(1) wouldn't link since it depends on PAM which depends on
# ssh libraries when building with OPENSSH, and likewise for KERBEROS.
# All other variables used to build /usr/src live in src.opts.mk
# and variables from both files are documented in src.conf(5).
__DEFAULT_YES_OPTIONS = \
ASSERT_DEBUG \
DEBUG_FILES \
DOCCOMPRESS \
INCLUDES \
INSTALLLIB \
KERBEROS \
MAKE_CHECK_USE_SANDBOX \
MAN \
MANCOMPRESS \
NIS \
NLS \
OPENSSH \
PROFILE \
SSP \
SYMVER \
TESTS \
TOOLCHAIN \
WARNS
__DEFAULT_NO_OPTIONS = \
BIND_NOW \
CCACHE_BUILD \
CTF \
INSTALL_AS_USER \
PIE \
RETPOLINE \
STALE_STAGED
__DEFAULT_DEPENDENT_OPTIONS = \
MAKE_CHECK_USE_SANDBOX/TESTS \
STAGING_MAN/STAGING \
STAGING_PROG/STAGING \
STALE_STAGED/STAGING \
.include <bsd.mkopt.mk>
#
# Supported NO_* options (if defined, MK_* will be forced to "no",
# regardless of user's setting).
#
# These are transitional and will disappaer in the FreeBSD 12.
#
.for var in \
CTF \
DEBUG_FILES \
INSTALLLIB \
MAN \
PROFILE \
WARNS
.if defined(NO_${var})
.warning "NO_${var} is defined, but deprecated. Please use MK_${var}=no instead."
MK_${var}:=no
.endif
.endfor
.include <bsd.cpu.mk>
.endif # !_WITHOUT_SRCCONF
.endif