diff --git a/servers/rendering/shader_language.cpp b/servers/rendering/shader_language.cpp
index 7c4128b0e37..764d420a239 100644
--- a/servers/rendering/shader_language.cpp
+++ b/servers/rendering/shader_language.cpp
@@ -39,7 +39,7 @@
 
 #define HAS_WARNING(flag) (warning_flags & flag)
 
-int ShaderLanguage::instance_counter = 0;
+SafeNumeric<int> ShaderLanguage::instance_counter;
 
 String ShaderLanguage::get_operator_text(Operator p_op) {
 	static const char *op_names[OP_MAX] = { "==",
@@ -11597,7 +11597,7 @@ ShaderLanguage::ShaderLanguage() {
 	nodes = nullptr;
 	completion_class = TAG_GLOBAL;
 
-	if (instance_counter == 0) {
+	if (instance_counter.get() == 0) {
 		int idx = 0;
 		while (builtin_func_defs[idx].name) {
 			if (builtin_func_defs[idx].tag == SubClassTag::TAG_GLOBAL) {
@@ -11606,7 +11606,7 @@ ShaderLanguage::ShaderLanguage() {
 			idx++;
 		}
 	}
-	instance_counter++;
+	instance_counter.increment();
 
 #ifdef DEBUG_ENABLED
 	warnings_check_map.insert(ShaderWarning::UNUSED_CONSTANT, &used_constants);
@@ -11621,8 +11621,8 @@ ShaderLanguage::ShaderLanguage() {
 
 ShaderLanguage::~ShaderLanguage() {
 	clear();
-	instance_counter--;
-	if (instance_counter == 0) {
+	instance_counter.decrement();
+	if (instance_counter.get() == 0) {
 		global_func_set.clear();
 	}
 }
diff --git a/servers/rendering/shader_language.h b/servers/rendering/shader_language.h
index 4dade4d79fd..4e7642a7818 100644
--- a/servers/rendering/shader_language.h
+++ b/servers/rendering/shader_language.h
@@ -36,6 +36,7 @@
 #include "core/string/ustring.h"
 #include "core/templates/list.h"
 #include "core/templates/rb_map.h"
+#include "core/templates/safe_refcount.h"
 #include "core/typedefs.h"
 #include "core/variant/variant.h"
 #include "scene/resources/shader_include.h"
@@ -833,7 +834,7 @@ public:
 	static bool is_control_flow_keyword(String p_keyword);
 	static void get_builtin_funcs(List<String> *r_keywords);
 
-	static int instance_counter;
+	static SafeNumeric<int> instance_counter;
 
 	struct BuiltInInfo {
 		DataType type = TYPE_VOID;
diff --git a/servers/rendering/shader_preprocessor.cpp b/servers/rendering/shader_preprocessor.cpp
index 88ea74cdfcd..4a9d97fc4ad 100644
--- a/servers/rendering/shader_preprocessor.cpp
+++ b/servers/rendering/shader_preprocessor.cpp
@@ -1236,6 +1236,13 @@ ShaderPreprocessor::Define *ShaderPreprocessor::create_define(const String &p_bo
 	return define;
 }
 
+void ShaderPreprocessor::insert_builtin_define(String p_name, String p_value, State &p_state) {
+	Define *define = memnew(Define);
+	define->is_builtin = true;
+	define->body = p_value;
+	p_state.defines[p_name] = define;
+}
+
 void ShaderPreprocessor::clear_state() {
 	if (state != nullptr) {
 		for (const RBMap<String, Define *>::Element *E = state->defines.front(); E; E = E->next()) {
@@ -1332,30 +1339,19 @@ Error ShaderPreprocessor::preprocess(const String &p_code, const String &p_filen
 
 	// Built-in defines.
 	{
-		static HashMap<StringName, String> defines;
+		const String rendering_method = OS::get_singleton()->get_current_rendering_method();
 
-		if (defines.is_empty()) {
-			const String rendering_method = OS::get_singleton()->get_current_rendering_method();
-
-			if (rendering_method == "forward_plus") {
-				defines["CURRENT_RENDERER"] = _MKSTR(2);
-			} else if (rendering_method == "mobile") {
-				defines["CURRENT_RENDERER"] = _MKSTR(1);
-			} else { // gl_compatibility
-				defines["CURRENT_RENDERER"] = _MKSTR(0);
-			}
-
-			defines["RENDERER_COMPATIBILITY"] = _MKSTR(0);
-			defines["RENDERER_MOBILE"] = _MKSTR(1);
-			defines["RENDERER_FORWARD_PLUS"] = _MKSTR(2);
+		if (rendering_method == "forward_plus") {
+			insert_builtin_define("CURRENT_RENDERER", _MKSTR(2), pp_state);
+		} else if (rendering_method == "mobile") {
+			insert_builtin_define("CURRENT_RENDERER", _MKSTR(1), pp_state);
+		} else { // gl_compatibility
+			insert_builtin_define("CURRENT_RENDERER", _MKSTR(0), pp_state);
 		}
 
-		for (const KeyValue<StringName, String> &E : defines) {
-			Define *define = memnew(Define);
-			define->is_builtin = true;
-			define->body = E.value;
-			pp_state.defines[E.key] = define;
-		}
+		insert_builtin_define("RENDERER_COMPATIBILITY", _MKSTR(0), pp_state);
+		insert_builtin_define("RENDERER_MOBILE", _MKSTR(1), pp_state);
+		insert_builtin_define("RENDERER_FORWARD_PLUS", _MKSTR(2), pp_state);
 	}
 
 	Error err = preprocess(&pp_state, p_code, r_result);
diff --git a/servers/rendering/shader_preprocessor.h b/servers/rendering/shader_preprocessor.h
index b3d9594bcbb..e9319730f86 100644
--- a/servers/rendering/shader_preprocessor.h
+++ b/servers/rendering/shader_preprocessor.h
@@ -215,6 +215,7 @@ private:
 	void set_error(const String &p_error, int p_line);
 
 	static Define *create_define(const String &p_body);
+	void insert_builtin_define(String p_name, String p_value, State &p_state);
 
 	void clear_state();