Converting output from "-fdiagnostics-format=json" back to "-fdiagnostics-format=text"

[Christian Friedl]

Dear GCC List,

Is there any standard way to convert output from
"-fdiagnostics-format=json" back to output that you would normally get
with "-fdiagnostics-format=text"? I would like to implement a filter
because as far as I know, there is no feature like "diagnostic pragmas"
for gfortran.

Best,
Christian