diff --git a/.gitignore b/.gitignore
index 0d50e757..537478c0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,5 +7,5 @@ cmake-build-debug/
 src/bin/BuiltHamcoreFiles/
 tmp/
 .gitconfig
-
-
+CMakeCache.txt
+CMakeFiles/
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9eac7fd5..540aba12 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -4,4 +4,9 @@ project(SoftEtherVPN LANGUAGES C)
 
 set(default_build_type "Release")
 
+# Check that submodules are present only if source was downloaded with git
+if(EXISTS "${SoftEtherVPN_SOURCE_DIR}/.git" AND NOT EXISTS "${SoftEtherVPN_SOURCE_DIR}/src/Mayaqua/cpu_features/CMakeLists.txt")
+    message (FATAL_ERROR "Submodules are not initialized. Run\n\tgit submodule update --init --recursive")
+endif()
+
 add_subdirectory(src)