Why do I get 'identifier "single" is undefined' error when importing struct with 'single' elements using the 'Simulink.​importExte​rnalCTypes​' function?

I have a ".h" file where I define custom data types. In it, I define struct types with elements of 'double' type and 'single' type. Then I use the 'Simulink.importExternalCTypes' function to generate Simulink representations of my custom data types. This is successful for the structs with 'double' elements, but for the structs with 'single' elements, I receive the error message below.

Error using Simulink.importExternalCTypes

Custom code parsing failed with the messages:

exampleTypes.h: error: identifier "single" is undefined.

Why am I experiencing this error message?

Answer 1

[MathWorks Support Team]

The syntax in C for a single precision floating type number is 'float.' The C 'float' type corresponds to the Simulink 'single' base data type. Changing the element definitions from 'single' to 'float' in 'exampleTypes.h' will resolve this error message.