3 # Setup variables for the linker.
5 # LINKER_TYPE is the major type of linker. Currently binutils and lld support
8 # LINKER_VERSION is a numeric constant equal to:
9 # major * 10000 + minor * 100 + tiny
10 # It too can be overridden on the command line.
12 # LINKER_FEATURES may contain one or more of the following, based on
13 # linker support for that feature:
15 # - build-id: support for generating a Build-ID note
16 # - retpoline: support for generating PLT with retpoline speculative
17 # execution vulnerability mitigation
19 # LINKER_FREEBSD_VERSION is the linker's internal source version.
21 # These variables with an X_ prefix will also be provided if XLD is set.
23 # This file may be included multiple times, but only has effect the first time.
26 .if !target(__<bsd.linker.mk>__)
29 _ld_vars=LD $${_empty_var_}
30 .if !empty(_WANT_TOOLCHAIN_CROSS_VARS)
31 # Only the toplevel makefile needs to compute the X_LINKER_* variables.
35 .for ld X_ in ${_ld_vars}
36 .if ${ld} == "LD" || !empty(XLD)
37 # Try to import LINKER_TYPE and LINKER_VERSION from parent make.
38 # The value is only used/exported for the same environment that impacts
39 # LD and LINKER_* settings here.
40 _exported_vars= ${X_}LINKER_TYPE ${X_}LINKER_VERSION ${X_}LINKER_FEATURES \
41 ${X_}LINKER_FREEBSD_VERSION
42 ${X_}_ld_hash= ${${ld}}${MACHINE}${PATH}
43 ${X_}_ld_hash:= ${${X_}_ld_hash:hash}
44 # Only import if none of the vars are set somehow else.
46 .for var in ${_exported_vars}
51 .if ${_can_export} == yes
52 .for var in ${_exported_vars}
53 .if defined(${var}.${${X_}_ld_hash})
54 ${var}= ${${var}.${${X_}_ld_hash}}
59 .if ${ld} == "LD" || (${ld} == "XLD" && ${XLD} != ${LD})
60 .if !defined(${X_}LINKER_TYPE) || !defined(${X_}LINKER_VERSION)
61 _ld_version!= (${${ld}} --version || echo none) | sed -n 1p
62 .if ${_ld_version} == "none"
63 .warning Unable to determine linker type from ${ld}=${${ld}}
65 .if ${_ld_version:[1..2]} == "GNU ld"
67 ${X_}LINKER_FREEBSD_VERSION= 0
68 _v= ${_ld_version:M[1-9].[0-9]*:[1]}
69 .elif ${_ld_version:[1]} == "LLD"
71 _v= ${_ld_version:[2]}
72 ${X_}LINKER_FREEBSD_VERSION!= \
73 ${${ld}} --version | \
74 awk '$$3 ~ /FreeBSD/ {print substr($$4, 1, length($$4)-1)}'
76 .warning Unknown linker from ${ld}=${${ld}}: ${_ld_version}, defaulting to bfd
80 ${X_}LINKER_VERSION!= echo "${_v:M[1-9].[0-9]*}" | \
81 awk -F. '{print $$1 * 10000 + $$2 * 100 + $$3;}'
85 .if ${${X_}LINKER_TYPE} != "bfd" || ${${X_}LINKER_VERSION} > 21750
86 ${X_}LINKER_FEATURES+= build-id
87 ${X_}LINKER_FEATURES+= ifunc
89 .if ${${X_}LINKER_TYPE} == "lld" && ${${X_}LINKER_VERSION} >= 60000
90 ${X_}LINKER_FEATURES+= retpoline
95 X_LINKER_TYPE= ${LINKER_TYPE}
96 X_LINKER_VERSION= ${LINKER_VERSION}
97 X_LINKER_FEATURES= ${LINKER_FEATURES}
98 X_LINKER_FREEBSD_VERSION= ${LINKER_FREEBSD_VERSION}
99 .endif # ${ld} == "LD" || (${ld} == "XLD" && ${XLD} != ${LD})
101 # Export the values so sub-makes don't have to look them up again, using the
102 # hash key computed above.
103 .for var in ${_exported_vars}
104 ${var}.${${X_}_ld_hash}:= ${${var}}
105 .export-env ${var}.${${X_}_ld_hash}
106 .undef ${var}.${${X_}_ld_hash}
109 .endif # ${ld} == "LD" || !empty(XLD)
110 .endfor # .for ld in LD XLD
113 .endif # !target(__<bsd.linker.mk>__)