- Qt Creator Documentation
- Code Model
- Qt Creator 20.0.0-beta2

Clangd ◦ Completion

# Code Model

The code model offers services such as code completion, syntactic and semantic highlighting, and diagnostics.

To configure the C++ code model globally, go to Preferences > C++ > Code Model.

The following table summarizes the preferences.

Setting | Value
--- | ---
Interpret ambiguous headers as C headers | Instructs the code model to interpret ambiguous header files as C language files. Select this checkbox if you develop mainly using C.
Ignore precompiled headers | Clear this checkbox to process precompiled headers.
Use built-in preprocessor to show pre-processed files | Uses the built-in preprocessor to show the pre-processed source file in the editor.
Enable indexing | Turns on the built-in indexer. Clearing this checkbox severely limits the capabilities of the code model.
Do not index files greater than | To avoid out-of-memory crashes caused by indexing huge source files that are typically auto-generated by scripts or code, the size of files to index is limited to 5MB by default. To index all files, clear the checkbox.
Ignore files | To ignore files that match wildcard patterns, enter each wildcard pattern on a separate line in the field.

## Inspect preprocessed C++ code

To analyze the causes of compile errors or errors caused by wrong includes pulled in by dependencies or C++ macros expanding to something unexpected, select Show Preprocessed Source in the editor context menu.

This action expands all C++ macros to their actual code and removes code that is guarded by a currently inactive `#ifdef` statements.

If you clear Use built-in preprocessor to show pre-processed files, this action also expands all `"#include <foo.h>"` statements to their actual contents.

See also Configure C++ code model, Specify clangd settings, Clang code model, and Clangd.

Clangd ◦ Completion