Tools using function names in the first column

The GNU Coding Standards document says:

It is also important that function definitions run the function name in column one. It helps people search for function definitions, and also helps some tools recognize them. Thus, using Standard C syntax, the format is as follows:

static char *
concat (char *s1, char *s2)
{
    ...
}

Are the tools that benefit from this agreement currently widely used?

Please note that I am not asking if this agreement is better than the others in terms of readability or aesthetics - which largely depends on the opinion - are only the tools that extract it still used.