Index: llvm/utils/gn/secondary/clang-tools-extra/clangd/index/dex/dexp/BUILD.gn
===================================================================
--- /dev/null
+++ llvm/utils/gn/secondary/clang-tools-extra/clangd/index/dex/dexp/BUILD.gn
@@ -0,0 +1,13 @@
+executable("dexp") {
+  configs += [ "//llvm/utils/gn/build:clang_code" ]
+  deps = [
+    "//clang-tools-extra/clangd",
+    "//clang/lib/Basic",
+    "//llvm/lib/LineEditor",
+    "//llvm/lib/Support",
+  ]
+  include_dirs = [ "../../.." ]
+  sources = [
+    "Dexp.cpp",
+  ]
+}
Index: llvm/utils/gn/secondary/clang-tools-extra/test/BUILD.gn
===================================================================
--- llvm/utils/gn/secondary/clang-tools-extra/test/BUILD.gn
+++ llvm/utils/gn/secondary/clang-tools-extra/test/BUILD.gn
@@ -74,6 +74,7 @@
     "//clang-tools-extra/clang-query/tool:clang-query",
     "//clang-tools-extra/clang-reorder-fields/tool:clang-reorder-fields",
     "//clang-tools-extra/clang-tidy/tool:clang-tidy",
+    "//clang-tools-extra/clangd/index/dex/dexp",
     "//clang-tools-extra/clangd/indexer:clangd-indexer",
     "//clang-tools-extra/clangd/tool:clangd",
     "//clang-tools-extra/modularize",
@@ -93,8 +94,6 @@
     deps +=
         [ "//clang-tools-extra/clangd/xpc/test-client:clangd-xpc-test-client" ]
   }
-
-  # FIXME: dep on dexp once it exist
   testonly = true
 }