sys-devel/clang: fix bootstrap on darwin prefix

Adjust the clang internal header/framework search paths when building on
darwin prefix. We symlink the selected MacOSX.sdk to EPREFIX/MacOSX.sdk
during bootstrap, so that is the correct place to get system headers,
such as those for libc, or for system framework headers, that we do not
replace in prefix.

Bug: https://bugs.gentoo.org/758167
Signed-off-by: Jacob Floyd <cognifloyd@gmail.com>
Signed-off-by: Fabian Groffen <grobian@gentoo.org>

6 files changed, 126 insertions, 6 deletions

diff --git a/sys-devel/clang/clang-11.0.0.ebuild b/sys-devel/clang/clang-11.0.0.ebuild
index cf0dde1f1604..1d4f4bad16c9 100644
--- a/sys-devel/clang/clang-11.0.0.ebuild
+++ b/sys-devel/clang/clang-11.0.0.ebuild
@@ -5,7 +5,7 @@ EAPI=7
 
 PYTHON_COMPAT=( python3_{6..9} )
 inherit cmake llvm llvm.org multilib-minimal pax-utils \
-	python-single-r1 toolchain-funcs
+	prefix python-single-r1 toolchain-funcs
 
 DESCRIPTION="C language family frontend for LLVM"
 HOMEPAGE="https://llvm.org/"
@@ -30,7 +30,7 @@ ALL_LLVM_TARGETS=( "${ALL_LLVM_TARGETS[@]/#/llvm_targets_}" )
 
 LICENSE="Apache-2.0-with-LLVM-exceptions UoI-NCSA MIT"
 SLOT="$(ver_cut 1)"
-KEYWORDS="amd64 arm arm64 ppc64 ~riscv x86 ~amd64-linux"
+KEYWORDS="amd64 arm arm64 ppc64 ~riscv x86 ~amd64-linux ~x64-macos"
 IUSE="debug default-compiler-rt default-libcxx default-lld
 	doc +static-analyzer test xml kernel_FreeBSD ${ALL_LLVM_TARGETS[*]}"
 REQUIRED_USE="${PYTHON_REQUIRED_USE}
@@ -75,6 +75,10 @@ PDEPEND="
 # Therefore: use sys-devel/clang[${MULTILIB_USEDEP}] only if you need
 # multilib clang* libraries (not runtime, not wrappers).
 
+PATCHES=(
+	"${FILESDIR}"/9999/prefix-dirs.patch
+)
+
 pkg_setup() {
 	LLVM_MAX_SLOT=${SLOT} llvm_pkg_setup
 	python-single-r1_pkg_setup
@@ -88,6 +92,11 @@ src_prepare() {
 	llvm.org_src_prepare
 
 	mv ../clang-tools-extra tools/extra || die
+
+	# add Gentoo Portage Prefix for Darwin (see prefix-dirs.patch)
+	eprefixify \
+		lib/Frontend/InitHeaderSearch.cpp \
+		lib/Driver/ToolChains/Darwin.cpp || die
 }
 
 check_distribution_components() {
diff --git a/sys-devel/clang/clang-11.0.1.9999.ebuild b/sys-devel/clang/clang-11.0.1.9999.ebuild
index 4a3a05b4df86..c5362450b519 100644
--- a/sys-devel/clang/clang-11.0.1.9999.ebuild
+++ b/sys-devel/clang/clang-11.0.1.9999.ebuild
@@ -5,7 +5,7 @@ EAPI=7
 
 PYTHON_COMPAT=( python3_{6..9} )
 inherit cmake llvm llvm.org multilib-minimal pax-utils \
-	python-single-r1 toolchain-funcs
+	prefix python-single-r1 toolchain-funcs
 
 DESCRIPTION="C language family frontend for LLVM"
 HOMEPAGE="https://llvm.org/"
@@ -77,6 +77,10 @@ llvm.org_set_globals
 # Therefore: use sys-devel/clang[${MULTILIB_USEDEP}] only if you need
 # multilib clang* libraries (not runtime, not wrappers).
 
+PATCHES=(
+	"${FILESDIR}"/9999/prefix-dirs.patch
+)
+
 pkg_setup() {
 	LLVM_MAX_SLOT=${SLOT} llvm_pkg_setup
 	python-single-r1_pkg_setup
@@ -90,6 +94,11 @@ src_prepare() {
 	llvm.org_src_prepare
 
 	mv ../clang-tools-extra tools/extra || die
+
+	# add Gentoo Portage Prefix for Darwin (see prefix-dirs.patch)
+	eprefixify \
+		lib/Frontend/InitHeaderSearch.cpp \
+		lib/Driver/ToolChains/Darwin.cpp || die
 }
 
 check_distribution_components() {
diff --git a/sys-devel/clang/clang-11.0.1_rc1.ebuild b/sys-devel/clang/clang-11.0.1_rc1.ebuild
index 4a3a05b4df86..c5362450b519 100644
--- a/sys-devel/clang/clang-11.0.1_rc1.ebuild
+++ b/sys-devel/clang/clang-11.0.1_rc1.ebuild
@@ -5,7 +5,7 @@ EAPI=7
 
 PYTHON_COMPAT=( python3_{6..9} )
 inherit cmake llvm llvm.org multilib-minimal pax-utils \
-	python-single-r1 toolchain-funcs
+	prefix python-single-r1 toolchain-funcs
 
 DESCRIPTION="C language family frontend for LLVM"
 HOMEPAGE="https://llvm.org/"
@@ -77,6 +77,10 @@ llvm.org_set_globals
 # Therefore: use sys-devel/clang[${MULTILIB_USEDEP}] only if you need
 # multilib clang* libraries (not runtime, not wrappers).
 
+PATCHES=(
+	"${FILESDIR}"/9999/prefix-dirs.patch
+)
+
 pkg_setup() {
 	LLVM_MAX_SLOT=${SLOT} llvm_pkg_setup
 	python-single-r1_pkg_setup
@@ -90,6 +94,11 @@ src_prepare() {
 	llvm.org_src_prepare
 
 	mv ../clang-tools-extra tools/extra || die
+
+	# add Gentoo Portage Prefix for Darwin (see prefix-dirs.patch)
+	eprefixify \
+		lib/Frontend/InitHeaderSearch.cpp \
+		lib/Driver/ToolChains/Darwin.cpp || die
 }
 
 check_distribution_components() {
diff --git a/sys-devel/clang/clang-11.0.1_rc2.ebuild b/sys-devel/clang/clang-11.0.1_rc2.ebuild
index 4a3a05b4df86..c5362450b519 100644
--- a/sys-devel/clang/clang-11.0.1_rc2.ebuild
+++ b/sys-devel/clang/clang-11.0.1_rc2.ebuild
@@ -5,7 +5,7 @@ EAPI=7
 
 PYTHON_COMPAT=( python3_{6..9} )
 inherit cmake llvm llvm.org multilib-minimal pax-utils \
-	python-single-r1 toolchain-funcs
+	prefix python-single-r1 toolchain-funcs
 
 DESCRIPTION="C language family frontend for LLVM"
 HOMEPAGE="https://llvm.org/"
@@ -77,6 +77,10 @@ llvm.org_set_globals
 # Therefore: use sys-devel/clang[${MULTILIB_USEDEP}] only if you need
 # multilib clang* libraries (not runtime, not wrappers).
 
+PATCHES=(
+	"${FILESDIR}"/9999/prefix-dirs.patch
+)
+
 pkg_setup() {
 	LLVM_MAX_SLOT=${SLOT} llvm_pkg_setup
 	python-single-r1_pkg_setup
@@ -90,6 +94,11 @@ src_prepare() {
 	llvm.org_src_prepare
 
 	mv ../clang-tools-extra tools/extra || die
+
+	# add Gentoo Portage Prefix for Darwin (see prefix-dirs.patch)
+	eprefixify \
+		lib/Frontend/InitHeaderSearch.cpp \
+		lib/Driver/ToolChains/Darwin.cpp || die
 }
 
 check_distribution_components() {
diff --git a/sys-devel/clang/clang-12.0.0.9999.ebuild b/sys-devel/clang/clang-12.0.0.9999.ebuild
index e5da1c5cedb4..8ebb9ceea5ec 100644
--- a/sys-devel/clang/clang-12.0.0.9999.ebuild
+++ b/sys-devel/clang/clang-12.0.0.9999.ebuild
@@ -5,7 +5,7 @@ EAPI=7
 
 PYTHON_COMPAT=( python3_{6..9} )
 inherit cmake llvm llvm.org multilib-minimal pax-utils \
-	python-single-r1 toolchain-funcs
+	prefix python-single-r1 toolchain-funcs
 
 DESCRIPTION="C language family frontend for LLVM"
 HOMEPAGE="https://llvm.org/"
@@ -77,6 +77,10 @@ llvm.org_set_globals
 # Therefore: use sys-devel/clang[${MULTILIB_USEDEP}] only if you need
 # multilib clang* libraries (not runtime, not wrappers).
 
+PATCHES=(
+	"${FILESDIR}"/9999/prefix-dirs.patch
+)
+
 pkg_setup() {
 	LLVM_MAX_SLOT=${SLOT} llvm_pkg_setup
 	python-single-r1_pkg_setup
@@ -88,6 +92,11 @@ src_prepare() {
 	BUILD_DIR=${WORKDIR}/x/y/clang
 
 	llvm.org_src_prepare
+
+	# add Gentoo Portage Prefix for Darwin (see prefix-dirs.patch)
+	eprefixify \
+		lib/Frontend/InitHeaderSearch.cpp \
+		lib/Driver/ToolChains/Darwin.cpp || die
 }
 
 check_distribution_components() {
diff --git a/sys-devel/clang/files/9999/prefix-dirs.patch b/sys-devel/clang/files/9999/prefix-dirs.patch
new file mode 100644
index 000000000000..0f7b5ca31ebc
--- /dev/null
+++ b/sys-devel/clang/files/9999/prefix-dirs.patch
@@ -0,0 +1,75 @@
+This mirrors cmake-*-prefix-dirs.patch
+
+It add EPREFIX to search paths for c/cxx headers.
+It also adds EPREFIX/MacOSX.sdk to search paths for c and Frameworks.
+Assumes that c++ lib and headers will be installed in the prefix.
+
+Also, a couple of args are populated by inspecting the SDK,
+so, default to EPREFIX/MacOSX.sdk when the sysroot is not specified.
+(This does NOT set sysroot).
+
+The ebuild adds an extra / at the end of EPREFIX so that it is never
+an empty string. 
+
+--- a/clang/lib/Frontend/InitHeaderSearch.cpp	2020-11-30 12:53:42.000000000 -0600
++++ b/clang/lib/Frontend/InitHeaderSearch.cpp	2020-11-30 13:57:52.000000000 -0600
+@@ -445,6 +445,9 @@
+   // All header search logic is handled in the Driver for Darwin.
+   if (triple.isOSDarwin()) {
+     if (HSOpts.UseStandardSystemIncludes) {
++      // Add Gentoo Prefix framework dirs first
++      AddPath("@GENTOO_PORTAGE_EPREFIX@MacOSX.sdk/System/Library/Frameworks", System, true);
++      AddPath("@GENTOO_PORTAGE_EPREFIX@MacOSX.sdk/Library/Frameworks", System, true);
+       // Add the default framework include paths on Darwin.
+       AddPath("/System/Library/Frameworks", System, true);
+       AddPath("/Library/Frameworks", System, true);
+--- a/clang/lib/Driver/ToolChains/Darwin.cpp	2020-10-07 05:10:48.000000000 -0500
++++ b/clang/lib/Driver/ToolChains/Darwin.cpp	2020-11-30 12:57:15.000000000 -0600
+@@ -1737,9 +1737,9 @@
+                                          const ArgList &Args,
+                                          const Driver &TheDriver) {
+   const Arg *A = Args.getLastArg(options::OPT_isysroot);
+-  if (!A)
+-    return None;
+-  StringRef isysroot = A->getValue();
++  //if (!A)
++  //  return None;
++  StringRef isysroot = A ? A->getValue() : "@GENTOO_PORTAGE_EPREFIX@MacOSX.sdk";
+   auto SDKInfoOrErr = driver::parseDarwinSDKInfo(VFS, isysroot);
+   if (!SDKInfoOrErr) {
+     llvm::consumeError(SDKInfoOrErr.takeError());
+@@ -1921,13 +1921,14 @@
+     return DriverArgs.getLastArgValue(options::OPT_isysroot);
+   if (!getDriver().SysRoot.empty())
+     return getDriver().SysRoot;
+-  return "/";
++  return "@GENTOO_PORTAGE_EPREFIX@";
+ }
+ 
+ void DarwinClang::AddClangSystemIncludeArgs(const llvm::opt::ArgList &DriverArgs,
+                                             llvm::opt::ArgStringList &CC1Args) const {
+   const Driver &D = getDriver();
+ 
++  // Sysroot is effectively Gentoo EPREFIX when -isysroot/-sysroot is not defined
+   llvm::StringRef Sysroot = GetHeaderSysroot(DriverArgs);
+ 
+   bool NoStdInc = DriverArgs.hasArg(options::OPT_nostdinc);
+@@ -1969,6 +1970,10 @@
+     SmallString<128> P(Sysroot);
+     llvm::sys::path::append(P, "usr", "include");
+     addExternCSystemInclude(DriverArgs, CC1Args, P.str());
++    // And add <sysroot>/MacOSX.sdk/usr/include.
++    SmallString<128> Psdk(Sysroot);
++    llvm::sys::path::append(Psdk, "MacOSX.sdk", "usr", "include");
++    addExternCSystemInclude(DriverArgs, CC1Args, Psdk.str());
+   }
+ }
+ 
+@@ -2017,6 +2022,7 @@
+       DriverArgs.hasArg(options::OPT_nostdincxx))
+     return;
+ 
++  // Sysroot is effectively Gentoo EPREFIX when -isysroot/-sysroot is not defined
+   llvm::StringRef Sysroot = GetHeaderSysroot(DriverArgs);
+ 
+   switch (GetCXXStdlibType(DriverArgs)) {