commit: 5912a8576845b68c850b9210c45f8aaaeede50a9 Author: Michał Górny <mgorny <AT> gentoo <DOT> org> AuthorDate: Mon Nov 3 17:29:23 2025 +0000 Commit: Michał Górny <mgorny <AT> gentoo <DOT> org> CommitDate: Fri Nov 7 02:38:44 2025 +0000 URL: https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=5912a857
fortran-2.eclass: Disable LTO if C+Fortran linking fails Try linking the code created by C and Fortran compilers together. If it fails, try removing LTO flags in case we are combining two incompatible compilers (Clang and GNU Fortran). Closes: https://bugs.gentoo.org/965176 Signed-off-by: Michał Górny <mgorny <AT> gentoo.org> Part-of: https://github.com/gentoo/gentoo/pull/44452 Closes: https://github.com/gentoo/gentoo/pull/44452 Signed-off-by: Michał Górny <mgorny <AT> gentoo.org> eclass/fortran-2.eclass | 92 ++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 83 insertions(+), 9 deletions(-) diff --git a/eclass/fortran-2.eclass b/eclass/fortran-2.eclass index dcf7ee979d8a..96849c0a743b 100644 --- a/eclass/fortran-2.eclass +++ b/eclass/fortran-2.eclass @@ -1,4 +1,4 @@ -# Copyright 1999-2024 Gentoo Authors +# Copyright 1999-2025 Gentoo Authors # Distributed under the terms of the GNU General Public License v2 # @ECLASS: fortran-2.eclass @@ -34,7 +34,7 @@ case ${EAPI} in *) die "${ECLASS}: EAPI ${EAPI:-0} not supported" ;; esac -inherit toolchain-funcs +inherit flag-o-matic toolchain-funcs # @ECLASS_VARIABLE: FORTRAN_NEED_OPENMP # @DESCRIPTION: @@ -187,6 +187,66 @@ _fortran-has-openmp() { return ${ret} } +# @FUNCTION: _fortran-test-lto +# @INTERNAL +# @DESCRIPTION: +# Test if C and Fortran files can be linked together. If it fails, remove +# LTO flags. This may be necessary if users are combining Clang +# with GNU Fortran, and enabling LTO, since this will result in two different +# kinds of bytecode being linked with a linker that's set up for only one +# of them. +_fortran-test-lto() { + debug-print-function ${FUNCNAME} "$@" + + local compiler=${1} + local flags=${2} + local fcode=${T}/test-fc.f + local ccode=${T}/test-fc.c + local fail= + + einfo "Testing linking C and Fortran code ..." + + cat <<- EOF > "${fcode}" || die + subroutine fsub() + end + EOF + cat <<- EOF > "${ccode}" || die + void fsub_(); + + int main() { + fsub_(); + return 0; + } + EOF + + # Prepare test objects. If either failed, do nothing. + + set -- ${compiler} ${flags} -c "${fcode}" -o "${fcode}.o" + echo "${@}" >&2 + "${@}" || return + + set -- $(tc-getCC) ${CFLAGS} -c "${ccode}" -o "${ccode}.o" + echo "${@}" >&2 + "${@}" || return + + # Try cross-linking. + + set -- ${compiler} ${flags} ${LDFLAGS} -o "${fcode}.exe" "${fcode}.o" "${ccode}.o" + echo "${@}" >&2 + "${@}" || fail=1 + + set -- $(tc-getCC) ${CFLAGS} ${LDFLAGS} -o "${fcode}.exe" "${fcode}.o" "${ccode}.o" + echo "${@}" >&2 + "${@}" || fail=1 + + if [[ ! ${fail} ]]; then + einfo "Looks like we can link C and Fortran code together" + else + einfo "Cross-linking C and Fortran failed, force-disabling LTO" + filter-lto + fi +} + # @FUNCTION: _fortran_die_msg # @INTERNAL # @DESCRIPTION: @@ -211,19 +271,31 @@ _fortran_die_msg() { _fortran_test_function() { debug-print-function ${FUNCNAME} "$@" - local dialect + local compiler dialect flags : "${F77:=$(tc-getFC)}" : "${FORTRAN_STANDARD:=77}" for dialect in ${FORTRAN_STANDARD}; do case ${dialect} in - 77) _fortran_compile_test "$(tc-getF77)" || \ - _fortran_die_msg ;; - 90|95) _fortran_compile_test "$(tc-getFC)" 90 || \ - _fortran_die_msg ;; - 2003) _fortran_compile_test "$(tc-getFC)" 03 || \ - _fortran_die_msg ;; + 77) + compiler=$(tc-getF77) + flags=${FFLAGS} + _fortran_compile_test "${compiler}" || + _fortran_die_msg + ;; + 90|95) + compiler=$(tc-getFC) + flags=${FCFLAGS} + _fortran_compile_test "${compiler}" 90 || + _fortran_die_msg + ;; + 2003) + compiler=$(tc-getFC) + flags=${FCFLAGS} + _fortran_compile_test "${compiler}" 03 || + _fortran_die_msg + ;; 2008) die "Future" ;; *) die "${dialect} is not a Fortran dialect." ;; esac @@ -241,6 +313,8 @@ _fortran_test_function() { die "Please install current gcc with USE=openmp or set the FC variable to a compiler that supports OpenMP" fi fi + + _fortran-test-lto "${compiler}" "${flags}" } # @FUNCTION: _fortran-2_pkg_setup
