2 # Setup variables for the linker.
4 # LINKER_TYPE is the major type of linker. Currently binutils and lld support
7 # LINKER_VERSION is a numeric constant equal to:
8 # major * 10000 + minor * 100 + tiny
9 # It too can be overridden on the command line.
11 # LINKER_FEATURES may contain one or more of the following, based on
12 # linker support for that feature:
14 # - build-id: support for generating a Build-ID note
15 # - retpoline: support for generating PLT with retpoline speculative
16 # execution vulnerability mitigation
18 # LINKER_FREEBSD_VERSION is the linker's internal source version.
20 # These variables with an X_ prefix will also be provided if XLD is set.
22 # This file may be included multiple times, but only has effect the first time.
25 .if !target(__<bsd.linker.mk>__)
28 _ld_vars=LD $${_empty_var_}
29 .if !empty(_WANT_TOOLCHAIN_CROSS_VARS)
30 # Only the toplevel makefile needs to compute the X_LINKER_* variables.
34 .for ld X_ in ${_ld_vars}
35 .if ${ld} == "LD" || !empty(XLD)
36 # Try to import LINKER_TYPE and LINKER_VERSION from parent make.
37 # The value is only used/exported for the same environment that impacts
38 # LD and LINKER_* settings here.
39 _exported_vars= ${X_}LINKER_TYPE ${X_}LINKER_VERSION ${X_}LINKER_FEATURES \
40 ${X_}LINKER_FREEBSD_VERSION
41 ${X_}_ld_hash= ${${ld}}${MACHINE}${PATH}
42 ${X_}_ld_hash:= ${${X_}_ld_hash:hash}
43 # Only import if none of the vars are set differently somehow else.
45 .for var in ${_exported_vars}
46 .if defined(${var}) && (!defined(${var}__${${X_}_ld_hash}) || ${${var}__${${X_}_ld_hash}} != ${${var}})
47 .if defined(${var}__${${X_}_ld_hash})
48 .info Cannot import ${X_}LINKER variables since cached ${var} is different: ${${var}__${${X_}_ld_hash}} != ${${var}}
53 .if ${_can_export} == yes
54 .for var in ${_exported_vars}
55 .if defined(${var}__${${X_}_ld_hash})
56 ${var}= ${${var}__${${X_}_ld_hash}}
61 .if ${ld} == "LD" || (${ld} == "XLD" && ${XLD} != ${LD})
62 .if !defined(${X_}LINKER_TYPE) || !defined(${X_}LINKER_VERSION)
63 _ld_version!= (${${ld}} -v 2>&1 || echo none) | sed -n 1p
64 .if ${_ld_version} == "none"
65 .warning Unable to determine linker type from ${ld}=${${ld}}
67 .if ${_ld_version:[1..2]} == "GNU ld"
69 ${X_}LINKER_FREEBSD_VERSION= 0
70 _v= ${_ld_version:M[1-9]*.[0-9]*:[1]}
71 .elif ${_ld_version:MLLD}
72 # Strip any leading PACKAGE_VENDOR string (e.g. "Homebrew")
73 _ld_version:=${_ld_version:[*]:C/^.* LLD /LLD /:[@]}
75 _v= ${_ld_version:[2]}
76 .if ${_ld_version:[3]} == "(FreeBSD"
77 ${X_}LINKER_FREEBSD_VERSION:= ${_ld_version:[4]:C/.*-([^-]*)\)/\1/}
79 ${X_}LINKER_FREEBSD_VERSION= 0
81 .elif ${_ld_version:[1]:S/-classic$//} == "@(\#)PROGRAM:ld"
82 # bootstrap linker on MacOS
84 _v= ${_ld_version:[2]:C/PROJECT:(ld64|dyld)-//}
85 # Convert version 409.12 to 409.12.0 so that the echo + awk below works
86 .if empty(_v:M[1-9]*.[0-9]*.[0-9]*) && !empty(_v:M[1-9]*.[0-9]*)
89 # Some versions do not contain a minor version so we need to append .0.0 there
93 .warning Unknown linker from ${ld}=${${ld}}: ${_ld_version}, defaulting to bfd
97 ${X_}LINKER_VERSION!= echo "${_v:M[1-9]*.[0-9]*}" | \
98 awk -F. '{print $$1 * 10000 + $$2 * 100 + $$3;}'
101 ${X_}LINKER_FEATURES=
102 .if ${${X_}LINKER_TYPE} != "bfd" || ${${X_}LINKER_VERSION} > 21750
103 ${X_}LINKER_FEATURES+= build-id
104 ${X_}LINKER_FEATURES+= ifunc
106 .if ${${X_}LINKER_TYPE} == "bfd" && ${${X_}LINKER_VERSION} > 21750
107 ${X_}LINKER_FEATURES+= riscv-relaxations
109 .if ${${X_}LINKER_TYPE} == "lld" && ${${X_}LINKER_VERSION} >= 60000
110 ${X_}LINKER_FEATURES+= retpoline
112 .if ${${X_}LINKER_TYPE} == "lld" && ${${X_}LINKER_VERSION} >= 90000
113 ${X_}LINKER_FEATURES+= ifunc-noplt
118 X_LINKER_TYPE= ${LINKER_TYPE}
119 X_LINKER_VERSION= ${LINKER_VERSION}
120 X_LINKER_FEATURES= ${LINKER_FEATURES}
121 X_LINKER_FREEBSD_VERSION= ${LINKER_FREEBSD_VERSION}
122 .endif # ${ld} == "LD" || (${ld} == "XLD" && ${XLD} != ${LD})
124 # Export the values so sub-makes don't have to look them up again, using the
125 # hash key computed above.
126 .for var in ${_exported_vars}
127 ${var}__${${X_}_ld_hash}:= ${${var}}
128 .export-env ${var}__${${X_}_ld_hash}
129 .undef ${var}__${${X_}_ld_hash}
132 .endif # ${ld} == "LD" || !empty(XLD)
133 .endfor # .for ld in LD XLD
136 .endif # !target(__<bsd.linker.mk>__)