diff --git a/src/lsp.hh b/src/lsp.hh
index b92578b8..b474fee0 100644
--- a/src/lsp.hh
+++ b/src/lsp.hh
@@ -261,6 +261,13 @@ struct ShowMessageParam {
 // Used to identify the language at a file level. The ordering is important, as
 // a file previously identified as `C`, will be changed to `Cpp` if it
 // encounters a c++ declaration.
-enum class LanguageId { Unknown = -1, C = 0, Cpp = 1, ObjC = 2, ObjCpp = 3 };
+enum class LanguageId {
+  Unknown = -1,
+  C = 0,
+  Cpp = 1,
+  ObjC = 2,
+  ObjCpp = 3,
+  Cuda = 4,
+};
 
 } // namespace ccls
diff --git a/src/project.cc b/src/project.cc
index fca2bb83..43fedd7b 100644
--- a/src/project.cc
+++ b/src/project.cc
@@ -60,7 +60,8 @@ std::pair<LanguageId, bool> lookupExtension(std::string_view filename) {
   bool objc = types::isObjC(I);
   LanguageId ret;
   if (types::isCXX(I))
-    ret = objc ? LanguageId::ObjCpp : LanguageId::Cpp;
+    ret = types::isCuda(I) ? LanguageId::Cuda
+                           : objc ? LanguageId::ObjCpp : LanguageId::Cpp;
   else if (objc)
     ret = LanguageId::ObjC;
   else if (I == types::TY_C || I == types::TY_CHeader)
@@ -117,6 +118,8 @@ struct ProjectProcessor {
             ok |= lang == LanguageId::C && header;
           else if (A.consume_front("%cpp "))
             ok |= lang == LanguageId::Cpp;
+          else if (A.consume_front("%cu "))
+            ok |= lang == LanguageId::Cuda;
           else if (A.consume_front("%hpp "))
             ok |= lang == LanguageId::Cpp && header;
           else if (A.consume_front("%objective-c "))
@@ -128,6 +131,9 @@ struct ProjectProcessor {
         }
         if (ok)
           args.push_back(A.data());
+      } else if (A.startswith("-M")) {
+        if (A == "-MF" || A == "-MT" || A == "-MQ")
+          i++;
       } else if (!ExcludesArg(A)) {
         args.push_back(arg);
       }