Distinguishs between dynamic library not found and can't be opened.

core/extension/gdextension.cpp

@@ -715,10 +715,8 @@ Error GDExtension::open_library(const String &p_path, const String &p_entry_symb
 #endif
 
 	Error err = OS::get_singleton()->open_dynamic_library(abs_path, library, true, &library_path);
-	if (err != OK) {
-		ERR_PRINT("GDExtension dynamic library not found: " + abs_path);
-		return err;
-	}
+	ERR_FAIL_COND_V_MSG(err == ERR_FILE_NOT_FOUND, err, "GDExtension dynamic library not found: " + abs_path);
+	ERR_FAIL_COND_V_MSG(err != OK, err, "Can't open GDExtension dynamic library: " + abs_path);
 
 #if defined(WINDOWS_ENABLED) && defined(TOOLS_ENABLED)
 	// If we copied the file, let's change the library path to point at the original,

drivers/unix/os_unix.cpp

@@ -656,6 +656,8 @@ Error OS_Unix::open_dynamic_library(const String p_path, void *&p_library_handle
 		path = get_executable_path().get_base_dir().path_join("../lib").path_join(p_path.get_file());
 	}
 
+	ERR_FAIL_COND_V(!FileAccess::exists(path), ERR_FILE_NOT_FOUND);
+
 	p_library_handle = dlopen(path.utf8().get_data(), GODOT_DLOPEN_MODE);
 	ERR_FAIL_NULL_V_MSG(p_library_handle, ERR_CANT_OPEN, vformat("Can't open dynamic library: %s. Error: %s.", p_path, dlerror()));
 

platform/android/os_android.cpp

@@ -170,6 +170,8 @@ Error OS_Android::open_dynamic_library(const String p_path, void *&p_library_han
 		so_file_exists = false;
 	}
 
+	ERR_FAIL_COND_V(!FileAccess::exists(path), ERR_FILE_NOT_FOUND);
+
 	p_library_handle = dlopen(path.utf8().get_data(), RTLD_NOW);
 	if (!p_library_handle && so_file_exists) {
 		// The library may be on the sdcard and thus inaccessible. Try to copy it to the internal

platform/ios/os_ios.mm

@@ -257,6 +257,8 @@ Error OS_IOS::open_dynamic_library(const String p_path, void *&p_library_handle,
 		path = get_framework_executable(get_executable_path().get_base_dir().path_join("Frameworks").path_join(p_path.get_file().get_basename() + ".framework"));
 	}
 
+	ERR_FAIL_COND_V(!FileAccess::exists(path), ERR_FILE_NOT_FOUND);
+
 	p_library_handle = dlopen(path.utf8().get_data(), RTLD_NOW);
 	ERR_FAIL_NULL_V_MSG(p_library_handle, ERR_CANT_OPEN, vformat("Can't open dynamic library: %s. Error: %s.", p_path, dlerror()));
 

platform/macos/os_macos.mm

@@ -230,6 +230,8 @@ Error OS_MacOS::open_dynamic_library(const String p_path, void *&p_library_handl
 		path = get_framework_executable(get_executable_path().get_base_dir().path_join("../Frameworks").path_join(p_path.get_file()));
 	}
 
+	ERR_FAIL_COND_V(!FileAccess::exists(path), ERR_FILE_NOT_FOUND);
+
 	p_library_handle = dlopen(path.utf8().get_data(), RTLD_NOW);
 	ERR_FAIL_NULL_V_MSG(p_library_handle, ERR_CANT_OPEN, vformat("Can't open dynamic library: %s. Error: %s.", p_path, dlerror()));
 

platform/windows/os_windows.cpp

@@ -360,6 +360,8 @@ Error OS_Windows::open_dynamic_library(const String p_path, void *&p_library_han
 		path = get_executable_path().get_base_dir().path_join(p_path.get_file());
 	}
 
+	ERR_FAIL_COND_V(!FileAccess::exists(path), ERR_FILE_NOT_FOUND);
+
 	typedef DLL_DIRECTORY_COOKIE(WINAPI * PAddDllDirectory)(PCWSTR);
 	typedef BOOL(WINAPI * PRemoveDllDirectory)(DLL_DIRECTORY_COOKIE);