1 2# Setup variables for the linker. 3# 4# LINKER_TYPE is the major type of linker. Currently binutils and lld support 5# automatic detection. 6# 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. 10# 11# LINKER_FEATURES may contain one or more of the following, based on 12# linker support for that feature: 13# 14# - build-id: support for generating a Build-ID note 15# - retpoline: support for generating PLT with retpoline speculative 16# execution vulnerability mitigation 17# 18# LINKER_FREEBSD_VERSION is the linker's internal source version. 19# 20# These variables with an X_ prefix will also be provided if XLD is set. 21# 22# This file may be included multiple times, but only has effect the first time. 23# 24 25.if !target(__<bsd.linker.mk>__) 26__<bsd.linker.mk>__: 27 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. 31_ld_vars+=XLD X_ 32.endif 33 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. 44_can_export= yes 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}} 49.endif 50_can_export= no 51.endif 52.endfor 53.if ${_can_export} == yes 54.for var in ${_exported_vars} 55.if defined(${var}__${${X_}_ld_hash}) 56${var}= ${${var}__${${X_}_ld_hash}} 57.endif 58.endfor 59.endif 60 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}} 66.endif 67.if ${_ld_version:[1..2]} == "GNU ld" 68${X_}LINKER_TYPE= bfd 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 /:[@]} 74${X_}LINKER_TYPE= lld 75_v= ${_ld_version:[2]} 76.if ${_ld_version:[3]} == "(FreeBSD" 77${X_}LINKER_FREEBSD_VERSION:= ${_ld_version:[4]:C/.*-([^-]*)\)/\1/} 78.else 79${X_}LINKER_FREEBSD_VERSION= 0 80.endif 81.elif ${_ld_version:[1]:S/-classic$//} == "@(\#)PROGRAM:ld" 82# bootstrap linker on MacOS 83${X_}LINKER_TYPE= mac 84_v= ${_ld_version:[2]:C/PROJECT:(ld64|dyld)-//} 85# Convert version 409.12 to 409.12.0 so that the echo + awk below works 86.if empty(_v:M[1-9]*.[0-9]*.[0-9]*) && !empty(_v:M[1-9]*.[0-9]*) 87_v:=${_v}.0 88.else 89# Some versions do not contain a minor version so we need to append .0.0 there 90_v:=${_v}.0.0 91.endif 92.else 93.warning Unknown linker from ${ld}=${${ld}}: ${_ld_version}, defaulting to bfd 94${X_}LINKER_TYPE= bfd 95_v= 2.17.50 96.endif 97${X_}LINKER_VERSION!= echo "${_v:M[1-9]*.[0-9]*}" | \ 98 awk -F. '{print $$1 * 10000 + $$2 * 100 + $$3;}' 99.undef _ld_version 100.undef _v 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 105.endif 106.if ${${X_}LINKER_TYPE} == "bfd" && ${${X_}LINKER_VERSION} > 21750 107${X_}LINKER_FEATURES+= riscv-relaxations 108.endif 109.if ${${X_}LINKER_TYPE} == "lld" && ${${X_}LINKER_VERSION} >= 60000 110${X_}LINKER_FEATURES+= retpoline 111.endif 112.if ${${X_}LINKER_TYPE} == "lld" && ${${X_}LINKER_VERSION} >= 90000 113${X_}LINKER_FEATURES+= ifunc-noplt 114.endif 115.endif 116.else 117# Use LD's values 118X_LINKER_TYPE= ${LINKER_TYPE} 119X_LINKER_VERSION= ${LINKER_VERSION} 120X_LINKER_FEATURES= ${LINKER_FEATURES} 121X_LINKER_FREEBSD_VERSION= ${LINKER_FREEBSD_VERSION} 122.endif # ${ld} == "LD" || (${ld} == "XLD" && ${XLD} != ${LD}) 123 124# 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} 130.endfor 131 132.endif # ${ld} == "LD" || !empty(XLD) 133.endfor # .for ld in LD XLD 134 135 136.endif # !target(__<bsd.linker.mk>__) 137