# V3512\. AUTOSAR\. Literal suffixes should not contain lowercase characters\.

This diagnostic rule is based on the software development guidelines developed by [AUTOSAR](https://www.autosar.org/) \(AUTomotive Open System ARchitecture\)\.

All literal suffixes should be uppercase\.

Using lowercase suffixes obscures the code\. For example, you may confuse an 'l' suffix with the numeral one \(1\), which could cause various mistakes\.

Here are examples of literals triggering this warning:

```cpp
12l; 34.0f; 23u;
```

The warning is not issued when the literals are written in the following form:

```cpp
12L; 34.0F; 23U;
```