dev-lang/swift: fix swift-5.10.1 linker error on compiling IndexStore

Closes: https://bugs.gentoo.org/950708
Signed-off-by: Itai Ferber <itai@itaiferber.net>

dev-lang/swift/files/swift-5.10.1-r3/clang-indexstore-exports.patch

@@ -0,0 +1,48 @@
+# The following functions are all declared to be explicitly exported from
+# IndexStore via IndexStore.exports, but their declarations and implementations
+# are guarded by `#if INDEXSTORE_HAS_BLOCKS`, which is `0` on non-Darwin
+# platforms. They're not used on non-Darwin platforms, so not exporting them
+# avoids a linker failure.
+
+--- a/llvm-project/clang/tools/IndexStore/IndexStore.exports
++++ b/llvm-project/clang/tools/IndexStore/IndexStore.exports
+@@ -10,9 +10,7 @@
+ indexstore_store_dispose
+ indexstore_store_get_unit_modification_time
+ indexstore_store_get_unit_name_from_output_path
+-indexstore_store_units_apply
+ indexstore_store_units_apply_f
+-indexstore_store_set_unit_event_handler
+ indexstore_store_set_unit_event_handler_f
+ indexstore_store_start_unit_event_listening
+ indexstore_store_stop_unit_event_listening
+@@ -33,19 +31,13 @@
+ indexstore_occurrence_get_symbol
+ indexstore_occurrence_get_roles
+ indexstore_occurrence_get_line_col
+-indexstore_occurrence_relations_apply
+ indexstore_occurrence_relations_apply_f
+ indexstore_record_reader_create
+ indexstore_record_reader_dispose
+-indexstore_record_reader_search_symbols
+ indexstore_record_reader_search_symbols_f
+-indexstore_record_reader_symbols_apply
+ indexstore_record_reader_symbols_apply_f
+-indexstore_record_reader_occurrences_apply
+ indexstore_record_reader_occurrences_apply_f
+-indexstore_record_reader_occurrences_in_line_range_apply
+ indexstore_record_reader_occurrences_in_line_range_apply_f
+-indexstore_record_reader_occurrences_of_symbols_apply
+ indexstore_record_reader_occurrences_of_symbols_apply_f
+ indexstore_unit_dependency_get_kind
+ indexstore_unit_dependency_get_filepath
+@@ -68,9 +60,7 @@
+ indexstore_unit_reader_get_output_file
+ indexstore_unit_reader_get_sysroot_path
+ indexstore_unit_reader_get_target
+-indexstore_unit_reader_dependencies_apply
+ indexstore_unit_reader_dependencies_apply_f
+-indexstore_unit_reader_includes_apply
+ indexstore_unit_reader_includes_apply_f
+ indexstore_unit_reader_has_main_file
+ indexstore_unit_reader_is_debug_compilation

dev-lang/swift/swift-5.10.1-r3.ebuild

@@ -52,6 +52,7 @@ SRC_URI="
 PATCHES=(
 	"${FILESDIR}/${PF}/backport-swift-75662.patch"
 	"${FILESDIR}/${PF}/backtracing-noexecstack.patch"
+	"${FILESDIR}/${PF}/clang-indexstore-exports.patch"
 	"${FILESDIR}/${PF}/disable-libdispatch-werror.patch"
 	"${FILESDIR}/${PF}/link-ncurses-tinfo.patch"
 	"${FILESDIR}/${PF}/link-with-lld.patch"