[clang-scan-deps] Add clang-scan-deps to llvm-driver build

[MaskRay]

Looks great!

clang/tools/clang-scan-deps/CMakeLists.txt

 set(LLVM_LINK_COMPONENTS
   Core
   Option
   Support
   TargetParser
   )
 
 set(LLVM_TARGET_DEFINITIONS Opts.td)
 tablegen(LLVM Opts.inc -gen-opt-parser-defs)
 add_public_tablegen_target(ScanDepsOptsTableGen)
 
 add_clang_tool(clang-scan-deps
   ClangScanDeps.cpp
 
   DEPENDS
   ScanDepsOptsTableGen
+  GENERATE_DRIVER
   )
 
 set(CLANG_SCAN_DEPS_LIB_DEPS
   clangAST
   clangBasic
   clangDependencyScanning
   clangDriver
   clangFrontend

clang/tools/clang-scan-deps/ClangScanDeps.cpp

 #include "clang/Tooling/DependencyScanning/DependencyScanningWorker.h"
 #include "clang/Tooling/JSONCompilationDatabase.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/FileUtilities.h"
 #include "llvm/Support/InitLLVM.h"
 #include "llvm/Support/JSON.h"
+#include "llvm/Support/LLVMDriver.h"
 #include "llvm/Support/Program.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/ThreadPool.h"
 #include "llvm/Support/Threading.h"
 #include "llvm/TargetParser/Host.h"
 #include <mutex>
 #include <optional>
 #include <thread>
static std::string getModuleCachePath(ArrayRef<std::string> Args) {
   return std::string(Path);
 }
 
 // getCompilationDataBase - If -compilation-database is set, load the
 // compilation database from the specified file. Otherwise if the we're
 // generating P1689 format, trying to generate the compilation database
 // form specified command line after the positional parameter "--".
 static std::unique_ptr<tooling::CompilationDatabase>
-getCompilationDataBase(int argc, const char **argv, std::string &ErrorMessage) {
+getCompilationDataBase(int argc, char **argv, std::string &ErrorMessage) {
   llvm::InitLLVM X(argc, argv);
-  ParseArgs(argc, const_cast<char **>(argv));
+  ParseArgs(argc, argv);
 
   if (!CompilationDB.empty())
     return tooling::JSONCompilationDatabase::loadFromFile(
         CompilationDB, ErrorMessage,
         tooling::JSONCommandLineSyntax::AutoDetect);
 
   if (Format != ScanningOutputFormat::P1689) {
     llvm::errs() << "the --compilation-database option: must be specified at "
                     "least once!";
     return nullptr;
   }
 
   // Trying to get the input file, the output file and the command line options
   // from the positional parameter "--".
-  const char **DoubleDash = std::find(argv, argv + argc, StringRef("--"));
+  char **DoubleDash = std::find(argv, argv + argc, StringRef("--"));
   if (DoubleDash == argv + argc) {
     llvm::errs() << "The command line arguments is required after '--' in "
                     "P1689 per file mode.";
     return nullptr;
   }
 
   llvm::IntrusiveRefCntPtr<DiagnosticsEngine> Diags =
       CompilerInstance::createDiagnostics(new DiagnosticOptions);
getCompilationDataBase(int argc, char **argv, std::string &ErrorMessage) {
   private:
     tooling::CompileCommand Command;
   };
 
   return std::make_unique<InplaceCompilationDatabase>(
       FEOpts.Inputs[0].getFile(), OutputFile, CommandLine);
 }
 
-int main(int argc, const char **argv) {
+int clang_scan_deps_main(int argc, char **argv, const llvm::ToolContext &) {
   std::string ErrorMessage;
   std::unique_ptr<tooling::CompilationDatabase> Compilations =
       getCompilationDataBase(argc, argv, ErrorMessage);
   if (!Compilations) {
     llvm::errs() << ErrorMessage << "\n";
     return 1;
   }
 

llvm/utils/gn/secondary/clang/tools/clang-scan-deps/BUILD.gn

+import("//llvm/utils/gn/build/driver_executable.gni")
 import("//llvm/utils/TableGen/tablegen.gni")
 
 tablegen("Opts") {
   visibility = [ ":clang-scan-deps" ]
   args = [ "-gen-opt-parser-defs" ]
 }
 
-executable("clang-scan-deps") {
+driver_executable("clang-scan-deps") {
   configs += [ "//llvm/utils/gn/build:clang_code" ]
   deps = [
     ":Opts",
     "//clang/lib/AST",
     "//clang/lib/Basic",
     "//clang/lib/CodeGen",
     "//clang/lib/Driver",
     "//clang/lib/Frontend",

utils/bazel/llvm-project-overlay/clang/BUILD.bazel

tbl_outs = [(
         "-gen-opt-parser-defs",
         "tools/clang-scan-deps/Opts.inc",
     )],
     tblgen = "//llvm:llvm-tblgen",
     td_file = "tools/clang-scan-deps/Opts.td",
     td_srcs = [ "//llvm:include/llvm/Option/OptParser.td" ],
 )
 
+expand_template(
+    name = "clang-scan-deps-main",
+    out = "clang-scan-deps-driver.cpp",
+    substitutions = {
+        "@TOOL_NAME@": "clang_scan_deps",
+    },
+    template = "//llvm:cmake/modules/llvm-driver-template.cpp.in",
+)
+
 cc_binary(
     name = "clang-scan-deps",
-    srcs = glob(["tools/clang-scan-deps/*.cpp"]),
+    srcs = glob(["tools/clang-scan-deps/*.cpp"]) + ["clang-scan-deps-driver.cpp"],
     stamp = 0,
     deps = [
         ":driver",
         ":frontend",
         ":ScanDepsTableGen",
         ":tooling",
         ":tooling_dependency_scanning",
         "//llvm:Support",