profiles: add clang profile feature

Signed-off-by: Alex Revin <2b57@pm.me>
Closes: https://github.com/gentoo/gentoo/pull/23187
Signed-off-by: Andreas K. Hüttel <dilfridge@gentoo.org>

7 files changed, 121 insertions, 0 deletions

diff --git a/profiles/features/clang/eapi b/profiles/features/clang/eapi
new file mode 100644
index 000000000000..7f8f011eb73d
--- /dev/null
+++ b/profiles/features/clang/eapi
@@ -0,0 +1 @@
+7
diff --git a/profiles/features/clang/make.defaults b/profiles/features/clang/make.defaults
new file mode 100644
index 000000000000..014816b37253
--- /dev/null
+++ b/profiles/features/clang/make.defaults
@@ -0,0 +1,58 @@
+# use Clang as a primary compiler
+CC="clang"
+CXX="clang++"
+
+# libtool needs this
+LD="ld.lld"
+
+# linker flags
+LDFLAGS="${LDFLAGS} -fuse-ld=lld -rtlib=compiler-rt -unwindlib=libunwind -Wl,--as-needed"
+
+# hardening flags
+SOME_HARDENING_CFLAGS="-fPIC -fstack-protector-strong -D_FORTIFY_SOURCE=2"
+SOME_HARDENING_LDFLAGS="-Wl,-z,relro,-z,now -pie"
+
+# enable some hardening by default
+CFLAGS="${CFLAGS} ${SOME_HARDENING_FLAGS}"
+CXXFLAGS="${CXXFLAGS} ${SOME_HARDENING_FLAGS}"
+LDFLAGS="${LDFLAGS} ${SOME_HARDENING_LDFLAGS}"
+
+# use LLVM-provided binutils
+AR="llvm-ar"
+AS="llvm-as"
+NM="llvm-nm"
+STRIP="llvm-strip"
+RANLIB="llvm-ranlib"
+OBJCOPY="llvm-objcopy"
+STRINGS="llvm-strings"
+OBJDUMP="llvm-objdump"
+READELF="llvm-readelf"
+ADDR2LINE="llvm-addr2line"
+
+
+# bootstrap USE for stage1
+
+# curl needed by cmake
+BOOTSTRAP_USE="$BOOTSTRAP_USE ssl curl_ssl_openssl"
+
+# Clang needs this
+BOOTSTRAP_USE="${BOOTSTRAP_USE} python_single_target_python3_9"
+
+# sys-devel/llvm
+BOOTSTRAP_USE="${BOOTSTRAP_USE} -gold"
+
+# sys-devel/clang, sys-devel/clang-runtime, sys-libs/llvm-libunwind, sys-libs/libcxx, sys-libs/libcxxabi
+BOOTSTRAP_USE="${BOOTSTRAP_USE} compiler-rt clang libunwind"
+
+# sys-devel/clang
+BOOTSTRAP_USE="${BOOTSTRAP_USE} default-compiler-rt default-lld default-libcxx llvm-libunwind"
+
+# sys-devel/clang-runtime
+# sanitizers are disabled for now
+BOOTSTRAP_USE="${BOOTSTRAP_USE} libcxx -sanitize"
+
+# sys-libs/libcxxabi
+BOOTSTRAP_USE="${BOOTSTRAP_USE} libcxxabi"
+
+# llvm & clang: explicitly disable all extra targets, otherwise linking stage2 fails
+BOOTSTRAP_USE="${BOOTSTRAP_USE} -llvm_targets_BPF -llvm_targets_AMDGPU -llvm_targets_NVPTX -llvm_targets_BPF"
diff --git a/profiles/features/clang/package.mask b/profiles/features/clang/package.mask
new file mode 100644
index 000000000000..0b6b883d274a
--- /dev/null
+++ b/profiles/features/clang/package.mask
@@ -0,0 +1,16 @@
+# mask LLVM 13, since it breaks tcl, which breaks sqlite and so on
+
+>sys-devel/llvm-12.0.1
+>sys-devel/llvm-common-12.0.1
+
+>sys-libs/compiler-rt-12.0.1
+>sys-libs/compiler-rt-sanitizers-12.0.1
+
+>sys-devel/clang-12.0.1
+>sys-devel/clang-common-12.0.1
+>sys-devel/clang-runtime-12.0.1
+
+>sys-devel/lld-12.0.1
+>sys-libs/libcxx-12.0.1
+>sys-libs/libcxxabi-12.0.1
+>sys-libs/llvm-libunwind-12.0.1
diff --git a/profiles/features/clang/package.use b/profiles/features/clang/package.use
new file mode 100644
index 000000000000..5d568cb8cb66
--- /dev/null
+++ b/profiles/features/clang/package.use
@@ -0,0 +1,17 @@
+# use lld by default
+sys-devel/llvm -gold
+
+# use all defaults
+sys-devel/clang compiler-rt default-compiler-rt default-lld default-libcxx llvm-libunwind
+sys-libs/compiler-rt clang
+
+# disable sanitizers for now
+sys-devel/clang-runtime compiler-rt libcxx -sanitize
+# sys-libs/compiler-rt-sanitizers clang
+
+sys-libs/libcxx libunwind libcxxabi
+sys-libs/libcxxabi libunwind
+sys-libs/llvm-libunwind compiler-rt
+
+# libgcrypt doesn't like optimizations
+dev-libs/libgcrypt o-flag-munging
diff --git a/profiles/features/clang/packages b/profiles/features/clang/packages
new file mode 100644
index 000000000000..9536b85862f3
--- /dev/null
+++ b/profiles/features/clang/packages
@@ -0,0 +1,14 @@
+# now part of @system set
+*sys-devel/lld
+*sys-devel/llvm
+*sys-devel/clang
+*sys-libs/libcxx
+*sys-libs/libcxxabi
+*sys-libs/compiler-rt
+*sys-libs/llvm-libunwind
+
+# not needed with clang
+-*sys-devel/gcc
+-*sys-devel/gcc-config
+-*sys-devel/binutils
+-*sys-devel/binutils-config
diff --git a/profiles/features/clang/packages.build b/profiles/features/clang/packages.build
new file mode 100644
index 000000000000..fd1e69e329e3
--- /dev/null
+++ b/profiles/features/clang/packages.build
@@ -0,0 +1,14 @@
+# will be pulled by stage1
+sys-libs/compiler-rt
+sys-libs/libcxxabi
+sys-libs/libcxx
+sys-devel/llvm
+sys-devel/lld
+sys-devel/clang
+sys-libs/llvm-libunwind
+
+# remove gcc & friends
+-sys-devel/gcc
+-sys-devel/gcc-config
+-sys-devel/binutils
+-sys-devel/binutils-config
diff --git a/profiles/features/clang/use.force b/profiles/features/clang/use.force
new file mode 100644
index 000000000000..e671fa21003e
--- /dev/null
+++ b/profiles/features/clang/use.force
@@ -0,0 +1 @@
+clang