In QT Creator build issues are showed in window as readable, filterable, customizable list.
Example of build issues in Qt Creator:
But in CLion it just a text list with links to build issues.
Example of build issues in CLion:
How to view build issues in CLion more readable?
I think that the main reason is that Qt Creator uses the clang toolkit to gather semantic information about the code, while CLion has its own C++ parser. As such, CLion has a direct representation of the compiler errors and warnings, as you mention.
On the other hand, CLion is able to notify you of errors and warnings without compiling the code, immediately :-) This feature is called "Code inspection", is customizable and filterable, and will give you even more information than the compiler.
You can find it under Code | Inspect code...
.
Example output:
See also my other answer to a similar question.