.. doxygenfunction fails to recognize function with restrict keyword in parameters

[acagliano]

Initially posted this issue directly on Doxygen's repo before discovering it was an issue with Breathe, not doxygen.
doxygen/doxygen#10170

The function prototype I am attempting to import is this:
void cryptx_hazmat_powmod(uint8_t size, uint8_t *restrict base, uint24_t exp, const uint8_t *restrict mod);

When attempting to import a function from a file via .. doxygenfunction:: cryptx_hazmat_powmod, if that function contains the restrict keyword, the XML output is <type>const uint8_t *restrict</type> which is incorrect.

This issue occurs only with .. doxygenfunction, not .. doxygenfile.

Min-reproducible code is zipped below. I usually build by running the local-build.sh script.
issue.zip

[michaeljones]

Thanks for the report and for the very well prepared example.

I'm not so involved these days but I poked around a bit. It seems like the function directive uses Sphinx C++ Domain code to parse the signature and 'restrict' isn't a keyword in C++ so it fails. I'm afraid I've not been in that part of the code for a long time and I'm not sure why it is being done like that. I imagine it is necessary to support overloaded functions in C++ by allowing users to specify the full function signature which then needs to be parsed but that is having a negative impact here.

Someone would have to look into using the C domain where appropriate (or no domain at all where appropriate) to handle this case better.