1# $FreeBSD$ 2 3# Setup variables for the linker. 4# 5# LINKER_TYPE is the major type of linker. Currently binutils and lld support 6# automatic detection. 7# 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. 11# 12# LINKER_FEATURES may contain one or more of the following, based on 13# linker support for that feature: 14# 15# - build-id: support for generating a Build-ID note 16# - retpoline: support for generating PLT with retpoline speculative 17# execution vulnerability mitigation 18# 19# LINKER_FREEBSD_VERSION is the linker's internal source version. 20# 21# These variables with an X_ prefix will also be provided if XLD is set. 22# 23# This file may be included multiple times, but only has effect the first time. 24# 25 26.if !target(__<bsd.linker.mk>__) 27__<bsd.linker.mk>__: 28 29_ld_vars=LD $${_empty_var_} 30.if !empty(_WANT_TOOLCHAIN_CROSS_VARS) 31# Only the toplevel makefile needs to compute the X_LINKER_* variables. 32_ld_vars+=XLD X_ 33.endif 34 35.for ld X_ in ${_ld_vars} 36.if ${ld} == "LD" || !empty(XLD) 37# Try to import LINKER_TYPE and LINKER_VERSION from parent make. 38# The value is only used/exported for the same environment that impacts 39# LD and LINKER_* settings here. 40_exported_vars= ${X_}LINKER_TYPE ${X_}LINKER_VERSION ${X_}LINKER_FEATURES \ 41 ${X_}LINKER_FREEBSD_VERSION 42${X_}_ld_hash= ${${ld}}${MACHINE}${PATH} 43${X_}_ld_hash:= ${${X_}_ld_hash:hash} 44# Only import if none of the vars are set somehow else. 45_can_export= yes 46.for var in ${_exported_vars} 47.if defined(${var}) 48_can_export= no 49.endif 50.endfor 51.if ${_can_export} == yes 52.for var in ${_exported_vars} 53.if defined(${var}.${${X_}_ld_hash}) 54${var}= ${${var}.${${X_}_ld_hash}} 55.endif 56.endfor 57.endif 58 59.if ${ld} == "LD" || (${ld} == "XLD" && ${XLD} != ${LD}) 60.if !defined(${X_}LINKER_TYPE) || !defined(${X_}LINKER_VERSION) 61_ld_version!= (${${ld}} --version || echo none) | sed -n 1p 62.if ${_ld_version} == "none" 63.warning Unable to determine linker type from ${ld}=${${ld}} 64.endif 65.if ${_ld_version:[1..2]} == "GNU ld" 66${X_}LINKER_TYPE= bfd 67${X_}LINKER_FREEBSD_VERSION= 0 68_v= ${_ld_version:M[1-9].[0-9]*:[1]} 69.elif ${_ld_version:[1]} == "LLD" 70${X_}LINKER_TYPE= lld 71_v= ${_ld_version:[2]} 72${X_}LINKER_FREEBSD_VERSION!= \ 73 ${${ld}} --version | \ 74 awk '$$3 ~ /FreeBSD/ {print substr($$4, 1, length($$4)-1)}' 75.else 76.warning Unknown linker from ${ld}=${${ld}}: ${_ld_version}, defaulting to bfd 77${X_}LINKER_TYPE= bfd 78_v= 2.17.50 79.endif 80${X_}LINKER_VERSION!= echo "${_v:M[1-9].[0-9]*}" | \ 81 awk -F. '{print $$1 * 10000 + $$2 * 100 + $$3;}' 82.undef _ld_version 83.undef _v 84${X_}LINKER_FEATURES= 85.if ${${X_}LINKER_TYPE} != "bfd" || ${${X_}LINKER_VERSION} > 21750 86${X_}LINKER_FEATURES+= build-id 87${X_}LINKER_FEATURES+= ifunc 88.endif 89.if ${${X_}LINKER_TYPE} == "lld" && ${${X_}LINKER_VERSION} >= 60000 90${X_}LINKER_FEATURES+= retpoline 91.endif 92.endif 93.else 94# Use LD's values 95X_LINKER_TYPE= ${LINKER_TYPE} 96X_LINKER_VERSION= ${LINKER_VERSION} 97X_LINKER_FEATURES= ${LINKER_FEATURES} 98X_LINKER_FREEBSD_VERSION= ${LINKER_FREEBSD_VERSION} 99.endif # ${ld} == "LD" || (${ld} == "XLD" && ${XLD} != ${LD}) 100 101# 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} 107.endfor 108 109.endif # ${ld} == "LD" || !empty(XLD) 110.endfor # .for ld in LD XLD 111 112 113.endif # !target(__<bsd.linker.mk>__) 114