summaryrefslogtreecommitdiff
blob: 20569c4eb465fe9bc006f8721f3f0f5297147f77 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
# Copyright 1999-2022 Gentoo Authors
# Distributed under the terms of the GNU General Public License v2

EAPI=7

CMAKE_ECLASS=cmake
PYTHON_COMPAT=( python3_{8..10} )
inherit cmake-multilib llvm llvm.org python-any-r1 toolchain-funcs

DESCRIPTION="New implementation of the C++ standard library, targeting C++11"
HOMEPAGE="https://libcxx.llvm.org/"

LICENSE="Apache-2.0-with-LLVM-exceptions || ( UoI-NCSA MIT )"
SLOT="0"
KEYWORDS=""
IUSE="+libcxxabi +libunwind static-libs test"
REQUIRED_USE="libunwind? ( libcxxabi )"
RESTRICT="!test? ( test )"

RDEPEND="
	libcxxabi? ( ~sys-libs/libcxxabi-${PV}[libunwind=,static-libs?,${MULTILIB_USEDEP}] )
	!libcxxabi? ( >=sys-devel/gcc-4.7:=[cxx] )"
# llvm-6 for new lit options
# clang-3.9.0 installs necessary target symlinks unconditionally
# which removes the need for MULTILIB_USEDEP
DEPEND="${RDEPEND}
	>=sys-devel/llvm-6"
BDEPEND="
	test? (
		>=dev-util/cmake-3.16
		>=sys-devel/clang-3.9.0
		sys-devel/gdb[python]
		$(python_gen_any_dep 'dev-python/lit[${PYTHON_USEDEP}]')
	)"

DOCS=( CREDITS.TXT )

LLVM_COMPONENTS=( libcxx{,abi} llvm/{cmake,utils/llvm-lit} cmake )
LLVM_PATCHSET=9999-1
llvm.org_set_globals

python_check_deps() {
	has_version "dev-python/lit[${PYTHON_USEDEP}]"
}

pkg_setup() {
	# Darwin Prefix builds do not have llvm installed yet, so rely on
	# bootstrap-prefix to set the appropriate path vars to LLVM instead
	# of using llvm_pkg_setup.
	if [[ ${CHOST} != *-darwin* ]] || has_version dev-lang/llvm; then
		llvm_pkg_setup
	fi
	use test && python-any-r1_pkg_setup

	if ! use libcxxabi && ! tc-is-gcc ; then
		eerror "To build ${PN} against libsupc++, you have to use gcc. Other"
		eerror "compilers are not supported. Please set CC=gcc and CXX=g++"
		eerror "and try again."
		die
	fi
}

test_compiler() {
	$(tc-getCXX) ${CXXFLAGS} ${LDFLAGS} "${@}" -o /dev/null -x c++ - \
		<<<'int main() { return 0; }' &>/dev/null
}

src_configure() {
	# note: we need to do this before multilib kicks in since it will
	# alter the CHOST
	local cxxabi cxxabi_incs
	if use libcxxabi; then
		cxxabi=libcxxabi
		cxxabi_incs="${EPREFIX}/usr/include/libcxxabi"
	else
		local gcc_inc="${EPREFIX}/usr/lib/gcc/${CHOST}/$(gcc-fullversion)/include/g++-v$(gcc-major-version)"
		cxxabi=libsupc++
		cxxabi_incs="${gcc_inc};${gcc_inc}/${CHOST}"
	fi

	multilib-minimal_src_configure
}

multilib_src_configure() {
	# we want -lgcc_s for unwinder, and for compiler runtime when using
	# gcc, clang with gcc runtime (or any unknown compiler)
	local extra_libs=() want_gcc_s=ON want_compiler_rt=OFF
	if use libunwind; then
		# work-around missing -lunwind upstream
		extra_libs+=( -lunwind )
		# if we're using libunwind and clang with compiler-rt, we want
		# to link to compiler-rt instead of -lgcc_s
		if tc-is-clang; then
			local compiler_rt=$($(tc-getCC) ${CFLAGS} ${CPPFLAGS} \
			   ${LDFLAGS} -print-libgcc-file-name)
			if [[ ${compiler_rt} == *libclang_rt* ]]; then
				want_gcc_s=OFF
				want_compiler_rt=ON
				extra_libs+=( "${compiler_rt}" )
			fi
		fi
	elif [[ ${CHOST} == *-darwin* ]] && tc-is-clang; then
		# clang-based darwin prefix disables libunwind useflag during
		# bootstrap, because libunwind is not in the prefix yet.
		# override the default, though, because clang based libcxx
		# should never use gcc_s on Darwin.
		want_gcc_s=OFF
		# compiler_rt is not available in EPREFIX during bootstrap,
		# so we cannot link to it yet anyway, so keep the defaults
		# of want_compiler_rt=OFF and extra_libs=()
	fi

	# bootstrap: cmake is unhappy if compiler can't link to stdlib
	local nolib_flags=( -nodefaultlibs -lc )
	if ! test_compiler; then
		if test_compiler "${nolib_flags[@]}"; then
			local -x LDFLAGS="${LDFLAGS} ${nolib_flags[*]}"
			ewarn "${CXX} seems to lack runtime, trying with ${nolib_flags[*]}"
		fi
	fi

	local libdir=$(get_libdir)
	local mycmakeargs=(
		-DLIBCXX_LIBDIR_SUFFIX=${libdir#lib}
		-DLIBCXX_ENABLE_SHARED=ON
		-DLIBCXX_ENABLE_STATIC=$(usex static-libs)
		-DLIBCXX_CXX_ABI=${cxxabi}
		-DLIBCXX_CXX_ABI_INCLUDE_PATHS=${cxxabi_incs}
		# we're using our own mechanism for generating linker scripts
		-DLIBCXX_ENABLE_ABI_LINKER_SCRIPT=OFF
		-DLIBCXX_HAS_MUSL_LIBC=$(usex elibc_musl)
		-DLIBCXX_HAS_GCC_S_LIB=${want_gcc_s}
		-DLIBCXX_INCLUDE_TESTS=$(usex test)
		-DLIBCXX_USE_COMPILER_RT=${want_compiler_rt}
		-DLIBCXX_HAS_ATOMIC_LIB=${want_gcc_s}
		-DLIBCXX_TARGET_TRIPLE="${CHOST}"
		-DCMAKE_SHARED_LINKER_FLAGS="${extra_libs[*]} ${LDFLAGS}"
	)

	if use test; then
		local clang_path=$(type -P "${CHOST:+${CHOST}-}clang" 2>/dev/null)
		[[ -n ${clang_path} ]] || die "Unable to find ${CHOST}-clang for tests"

		mycmakeargs+=(
			-DLLVM_EXTERNAL_LIT="${EPREFIX}/usr/bin/lit"
			-DLLVM_LIT_ARGS="$(get_lit_flags);--param=cxx_under_test=${clang_path}"
			-DLIBCXX_LINK_TESTS_WITH_SHARED_LIBCXXABI=ON
			-DPython3_EXECUTABLE="${PYTHON}"
		)
	fi
	cmake_src_configure
}

multilib_src_test() {
	local -x LIT_PRESERVES_TMP=1
	cmake_build check-cxx
}

# Usage: deps
gen_ldscript() {
	local output_format
	output_format=$($(tc-getCC) ${CFLAGS} ${LDFLAGS} -Wl,--verbose 2>&1 | sed -n 's/^OUTPUT_FORMAT("\([^"]*\)",.*/\1/p')
	[[ -n ${output_format} ]] && output_format="OUTPUT_FORMAT ( ${output_format} )"

	cat <<-END_LDSCRIPT
/* GNU ld script
   Include missing dependencies
*/
${output_format}
GROUP ( $@ )
END_LDSCRIPT
}

gen_static_ldscript() {
	local libdir=$(get_libdir)
	local cxxabi_lib=$(usex libcxxabi "libc++abi.a" "libsupc++.a")

	# Move it first.
	mv "${ED}/usr/${libdir}/libc++.a" "${ED}/usr/${libdir}/libc++_static.a" || die
	# Generate libc++.a ldscript for inclusion of its dependencies so that
	# clang++ -stdlib=libc++ -static works out of the box.
	local deps="libc++_static.a ${cxxabi_lib} $(usex libunwind libunwind.a libgcc_eh.a)"
	# On Linux/glibc it does not link without libpthread or libdl. It is
	# fine on FreeBSD.
	use elibc_glibc && deps+=" libpthread.a libdl.a"

	gen_ldscript "${deps}" > "${ED}/usr/${libdir}/libc++.a" || die
}

gen_shared_ldscript() {
	local libdir=$(get_libdir)
	# libsupc++ doesn't have a shared version
	local cxxabi_lib=$(usex libcxxabi "libc++abi.so" "libsupc++.a")

	mv "${ED}/usr/${libdir}/libc++.so" "${ED}/usr/${libdir}/libc++_shared.so" || die
	local deps="libc++_shared.so ${cxxabi_lib} $(usex libunwind libunwind.so libgcc_s.so)"

	gen_ldscript "${deps}" > "${ED}/usr/${libdir}/libc++.so" || die
}

multilib_src_install() {
	cmake_src_install
	if [[ ${CHOST} != *-darwin* ]] ; then
		gen_shared_ldscript
		use static-libs && gen_static_ldscript
	fi
}

pkg_postinst() {
	elog "This package (${PN}) is mainly intended as a replacement for the C++"
	elog "standard library when using clang."
	elog "To use it, instead of libstdc++, use:"
	elog "    clang++ -stdlib=libc++"
	elog "to compile your C++ programs."
}