diff --git a/modules/gdnative/SCsub b/modules/gdnative/SCsub
index 66b8d5cbdd8..485bf4b9df0 100644
--- a/modules/gdnative/SCsub
+++ b/modules/gdnative/SCsub
@@ -49,19 +49,6 @@ def _build_gdnative_api_struct_header(api):
         'extern "C" {',
         '#endif',
         '',
-        'typedef struct godot_gdnative_api_version {',
-        '\tunsigned int major;',
-        '\tunsigned int minor;',
-        '} godot_gdnative_api_version;',
-        '',
-        'typedef struct godot_gdnative_api_struct godot_gdnative_api_struct;',
-        '',
-        'struct godot_gdnative_api_struct {',
-        '\tunsigned int type;',
-        '\tgodot_gdnative_api_version version;',
-        '\tconst godot_gdnative_api_struct *next;',
-        '};',
-        '',
         'enum GDNATIVE_API_TYPES {',
         '\tGDNATIVE_' + api['core']['type'] + ','
     ]
diff --git a/modules/gdnative/gdnative.cpp b/modules/gdnative/gdnative.cpp
index 44d6dffc851..7949ca182f5 100644
--- a/modules/gdnative/gdnative.cpp
+++ b/modules/gdnative/gdnative.cpp
@@ -109,6 +109,9 @@ Ref<GDNativeLibrary> GDNative::get_library() {
 	return library;
 }
 
+extern "C" void _gdnative_report_version_mismatch(const godot_object *p_library, const char *p_ext, godot_gdnative_api_version p_want, godot_gdnative_api_version p_have);
+extern "C" void _gdnative_report_loading_error(const godot_object *p_library, const char *p_what);
+
 bool GDNative::initialize() {
 	if (library.is_null()) {
 		ERR_PRINT("No library set, can't initialize GDNative object");
@@ -168,6 +171,8 @@ bool GDNative::initialize() {
 	options.core_api_hash = ClassDB::get_api_hash(ClassDB::API_CORE);
 	options.editor_api_hash = ClassDB::get_api_hash(ClassDB::API_EDITOR);
 	options.no_api_hash = ClassDB::get_api_hash(ClassDB::API_NONE);
+	options.report_version_mismatch = &_gdnative_report_version_mismatch;
+	options.report_loading_error = &_gdnative_report_loading_error;
 	options.gd_native_library = (godot_object *)(get_library().ptr());
 	options.active_library_path = (godot_string *)&path;
 
diff --git a/modules/gdnative/gdnative/gdnative.cpp b/modules/gdnative/gdnative/gdnative.cpp
index 6dfa7ec20bf..34b73558d52 100644
--- a/modules/gdnative/gdnative/gdnative.cpp
+++ b/modules/gdnative/gdnative/gdnative.cpp
@@ -36,6 +36,8 @@
 #include "os/os.h"
 #include "variant.h"
 
+#include "modules/gdnative/gdnative.h"
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -137,6 +139,32 @@ void GDAPI godot_print(const godot_string *p_message) {
 	print_line(*(String *)p_message);
 }
 
+void _gdnative_report_version_mismatch(const godot_object *p_library, const char *p_ext, godot_gdnative_api_version p_want, godot_gdnative_api_version p_have) {
+	String message = "Error loading GDNative file ";
+	GDNativeLibrary *library = (GDNativeLibrary *)p_library;
+
+	message += library->get_current_library_path() + ": Extension \"" + p_ext + "\" can't be loaded.\n";
+
+	Dictionary versions;
+	versions["have_major"] = p_have.major;
+	versions["have_minor"] = p_have.minor;
+	versions["want_major"] = p_want.major;
+	versions["want_minor"] = p_want.minor;
+
+	message += String("Got version {have_major}.{have_minor} but needs {want_major}.{want_minor}!").format(versions);
+
+	_err_print_error("gdnative_init", library->get_current_library_path().utf8().ptr(), 0, message.utf8().ptr());
+}
+
+void _gdnative_report_loading_error(const godot_object *p_library, const char *p_what) {
+	String message = "Error loading GDNative file ";
+	GDNativeLibrary *library = (GDNativeLibrary *)p_library;
+
+	message += library->get_current_library_path() + ": " + p_what;
+
+	_err_print_error("gdnative_init", library->get_current_library_path().utf8().ptr(), 0, message.utf8().ptr());
+}
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/modules/gdnative/gdnative/string.cpp b/modules/gdnative/gdnative/string.cpp
index 781b8754bd5..67a037736c9 100644
--- a/modules/gdnative/gdnative/string.cpp
+++ b/modules/gdnative/gdnative/string.cpp
@@ -89,11 +89,6 @@ wchar_t GDAPI godot_string_operator_index_const(const godot_string *p_self, cons
 	return self->operator[](p_idx);
 }
 
-const char GDAPI *godot_string_c_str(const godot_string *p_self) {
-	const String *self = (const String *)p_self;
-	return self->utf8().get_data();
-}
-
 const wchar_t GDAPI *godot_string_unicode_str(const godot_string *p_self) {
 	const String *self = (const String *)p_self;
 	return self->c_str();
diff --git a/modules/gdnative/gdnative_api.json b/modules/gdnative/gdnative_api.json
index 877c65dfb97..0a1c5095d4e 100644
--- a/modules/gdnative/gdnative_api.json
+++ b/modules/gdnative/gdnative_api.json
@@ -4361,13 +4361,6 @@
           ["const godot_int", "p_idx"]
         ]
       },
-      {
-        "name": "godot_string_c_str",
-        "return_type": "const char *",
-        "arguments": [
-          ["const godot_string *", "p_self"]
-        ]
-      },
       {
         "name": "godot_string_unicode_str",
         "return_type": "const wchar_t *",
diff --git a/modules/gdnative/include/gdnative/gdnative.h b/modules/gdnative/include/gdnative/gdnative.h
index 38a42ab6586..e8d509508e1 100644
--- a/modules/gdnative/include/gdnative/gdnative.h
+++ b/modules/gdnative/include/gdnative/gdnative.h
@@ -229,13 +229,28 @@ void GDAPI godot_method_bind_ptrcall(godot_method_bind *p_method_bind, godot_obj
 godot_variant GDAPI godot_method_bind_call(godot_method_bind *p_method_bind, godot_object *p_instance, const godot_variant **p_args, const int p_arg_count, godot_variant_call_error *p_call_error);
 ////// Script API
 
-struct godot_gdnative_api_struct; // Forward declaration
+typedef struct godot_gdnative_api_version {
+	unsigned int major;
+	unsigned int minor;
+} godot_gdnative_api_version;
+
+typedef struct godot_gdnative_api_struct godot_gdnative_api_struct;
+
+struct godot_gdnative_api_struct {
+	unsigned int type;
+	godot_gdnative_api_version version;
+	const godot_gdnative_api_struct *next;
+};
+
+#define GDNATIVE_VERSION_COMPATIBLE(want, have) (want.major == have.major && want.minor <= have.minor)
 
 typedef struct {
 	godot_bool in_editor;
 	uint64_t core_api_hash;
 	uint64_t editor_api_hash;
 	uint64_t no_api_hash;
+	void (*report_version_mismatch)(const godot_object *p_library, const char *p_what, godot_gdnative_api_version p_want, godot_gdnative_api_version p_have);
+	void (*report_loading_error)(const godot_object *p_library, const char *p_what);
 	godot_object *gd_native_library; // pointer to GDNativeLibrary that is being initialized
 	const struct godot_gdnative_core_api_struct *api_struct;
 	const godot_string *active_library_path;
diff --git a/modules/gdnative/include/gdnative/string.h b/modules/gdnative/include/gdnative/string.h
index cca3eb26723..10358ceade5 100644
--- a/modules/gdnative/include/gdnative/string.h
+++ b/modules/gdnative/include/gdnative/string.h
@@ -68,7 +68,6 @@ void GDAPI godot_string_get_data(const godot_string *p_self, char *p_dest, int *
 
 wchar_t GDAPI *godot_string_operator_index(godot_string *p_self, const godot_int p_idx);
 wchar_t GDAPI godot_string_operator_index_const(const godot_string *p_self, const godot_int p_idx);
-const char GDAPI *godot_string_c_str(const godot_string *p_self);
 const wchar_t GDAPI *godot_string_unicode_str(const godot_string *p_self);
 
 godot_bool GDAPI godot_string_operator_equal(const godot_string *p_self, const godot_string *p_b);