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 differently somehow else.
46 .for var in ${_exported_vars}
47 .if defined(${var}) && (!defined(${var}__${${X_}_ld_hash}) || ${${var}__${${X_}_ld_hash}} != ${${var}})
48 .if defined(${var}__${${X_}_ld_hash})
49 .info "Cannot import ${X_}LINKER variables since cached ${var} is different: ${${var}__${${X_}_ld_hash}} != ${${var}}"
54 .if ${_can_export} == yes
55 .for var in ${_exported_vars}
56 .if defined(${var}__${${X_}_ld_hash})
57 ${var}= ${${var}__${${X_}_ld_hash}}
62 .if ${ld} == "LD" || (${ld} == "XLD" && ${XLD} != ${LD})
63 .if !defined(${X_}LINKER_TYPE) || !defined(${X_}LINKER_VERSION)
64 _ld_version!= (${${ld}} -v 2>&1 || echo none) | sed -n 1p
65 .if ${_ld_version} == "none"
66 .warning Unable to determine linker type from ${ld}=${${ld}}
68 .if ${_ld_version:[1..2]} == "GNU ld"
70 ${X_}LINKER_FREEBSD_VERSION= 0
71 _v= ${_ld_version:M[1-9]*.[0-9]*:[1]}
72 .elif ${_ld_version:[1]} == "LLD"
74 _v= ${_ld_version:[2]}
75 .if ${_ld_version:[3]} == "(FreeBSD"
76 ${X_}LINKER_FREEBSD_VERSION:= ${_ld_version:[4]:C/.*-([^-]*)\)/\1/}
78 ${X_}LINKER_FREEBSD_VERSION= 0
80 .elif ${_ld_version:[1]} == "@(\#)PROGRAM:ld"
81 # bootstrap linker on MacOS
83 _v= ${_ld_version:[2]:S/PROJECT:ld64-//}
84 # Convert version 409.12 to 409.12.0 so that the echo + awk below works
85 .if empty(_v:M[1-9]*.[0-9]*.[0-9]*) && !empty(_v:M[1-9]*.[0-9]*)
88 # Some versions do not contain a minor version so we need to append .0.0 there
92 .warning Unknown linker from ${ld}=${${ld}}: ${_ld_version}, defaulting to bfd
96 ${X_}LINKER_VERSION!= echo "${_v:M[1-9]*.[0-9]*}" | \
97 awk -F. '{print $$1 * 10000 + $$2 * 100 + $$3;}'
100 ${X_}LINKER_FEATURES=
101 .if ${${X_}LINKER_TYPE} != "bfd" || ${${X_}LINKER_VERSION} > 21750
102 ${X_}LINKER_FEATURES+= build-id
103 ${X_}LINKER_FEATURES+= ifunc
105 .if ${${X_}LINKER_TYPE} == "bfd" && ${${X_}LINKER_VERSION} > 21750
106 ${X_}LINKER_FEATURES+= riscv-relaxations
108 .if ${${X_}LINKER_TYPE} == "lld" && ${${X_}LINKER_VERSION} >= 60000
109 ${X_}LINKER_FEATURES+= retpoline
111 .if ${${X_}LINKER_TYPE} == "lld" && ${${X_}LINKER_VERSION} >= 90000
112 ${X_}LINKER_FEATURES+= ifunc-noplt
117 X_LINKER_TYPE= ${LINKER_TYPE}
118 X_LINKER_VERSION= ${LINKER_VERSION}
119 X_LINKER_FEATURES= ${LINKER_FEATURES}
120 X_LINKER_FREEBSD_VERSION= ${LINKER_FREEBSD_VERSION}
121 .endif # ${ld} == "LD" || (${ld} == "XLD" && ${XLD} != ${LD})
123 # Export the values so sub-makes don't have to look them up again, using the
124 # hash key computed above.
125 .for var in ${_exported_vars}
126 ${var}__${${X_}_ld_hash}:= ${${var}}
127 .export-env ${var}__${${X_}_ld_hash}
128 .undef ${var}__${${X_}_ld_hash}
131 .endif # ${ld} == "LD" || !empty(XLD)
132 .endfor # .for ld in LD XLD
135 .endif # !target(__<bsd.linker.mk>__)