Get the location of a previous token in Clang

Clang Frontend
1

Dear Klimek ,

Could you please help me with the following question?

I am new to Clang and currently writing a libtooling tool.

Suppose a ‘pragma’ like following is registered:

#pragma tool

It is easily to get the location of token ‘tool’, but how to get the location
of token ‘pragma’ ? Which API should I use?

Thanks in advance!

Best

James