Fixes #423: now uses clang++ to find system include paths

src/compile_commands.cc

@@ -1,9 +1,35 @@
 #include "compile_commands.h"
 #include "clangmm.h"
+#include "terminal.h"
 #include <algorithm>
 #include <boost/property_tree/json_parser.hpp>
 #include <regex>
 
+CompileCommands::FindSystemIncludePaths::FindSystemIncludePaths() {
+  std::stringstream stdin_stream, stdout_stream;
+  stdin_stream << "int main() {}";
+  exit_status = Terminal::get().process(stdin_stream, stdout_stream, "clang++ -v -x c++ -E 2>&1 -");
+  if(exit_status != 0)
+    return;
+  std::string line;
+  while(std::getline(stdout_stream, line)) {
+    if(line == "#include <...> search starts here:") {
+      while(std::getline(stdout_stream, line)) {
+        if(!line.empty() && line[0] == ' ') {
+          auto end = line.find(" (framework directory)", 1);
+          if(end == std::string::npos)
+            include_paths.emplace_back(line.substr(1, end));
+          else
+            framework_paths.emplace_back(line.substr(1, end));
+        }
+        else
+          return;
+      }
+      return;
+    }
+  }
+}
+
 std::vector<std::string> CompileCommands::Command::parameter_values(const std::string &parameter_name) const {
   std::vector<std::string> parameter_values;
 
@@ -135,6 +161,14 @@ std::vector<std::string> CompileCommands::get_arguments(const boost::filesystem:
   else
     arguments.emplace_back(default_std_argument);
 
+  static FindSystemIncludePaths system_include_paths;
+  if(system_include_paths) {
+    for(auto &path : system_include_paths.include_paths)
+      arguments.emplace_back("-I" + path);
+    for(auto &path : system_include_paths.framework_paths)
+      arguments.emplace_back("-F" + path);
+  }
+  else {
     auto clang_version_string = clangmm::to_string(clang_getClangVersion());
     const static std::regex clang_version_regex(R"(^[A-Za-z ]+([0-9.]+).*$)");
     std::smatch sm;
@@ -155,6 +189,7 @@ std::vector<std::string> CompileCommands::get_arguments(const boost::filesystem:
         arguments.emplace_back("-I" + (boost::filesystem::path(env_msystem_prefix) / "lib/clang" / clang_version / "include").string());
 #endif
     }
+  }
 
   // Do not add -fretain-comments-from-system-headers if pch is used, since the pch was most likely made without this flag
   if(std::none_of(arguments.begin(), arguments.end(), [](const std::string &argument) { return argument == "-include-pch"; }))

src/compile_commands.h

@@ -5,6 +5,17 @@
 
 class CompileCommands {
 public:
+  class FindSystemIncludePaths {
+    int exit_status;
+
+  public:
+    std::vector<std::string> include_paths;
+    std::vector<std::string> framework_paths;
+    operator bool() const { return exit_status == 0; }
+
+    FindSystemIncludePaths();
+  };
+
   class Command {
   public:
     boost::filesystem::path directory;

tests/compile_commands_test.cc

@@ -1,9 +1,17 @@
 #include "compile_commands.h"
 #include <glib.h>
+#include <gtkmm.h>
 
 int main() {
+  auto app = Gtk::Application::create();
+
   auto tests_path = boost::filesystem::canonical(JUCI_TESTS_PATH);
 
+  {
+    CompileCommands::FindSystemIncludePaths system_include_paths;
+    g_assert(system_include_paths);
+    g_assert(!system_include_paths.include_paths.empty());
+  }
   {
     CompileCommands compile_commands(tests_path / "meson_test_files" / "build");