##### 15.4.1.4 C and C`++` Defaults

If you allow gdb to set type and range checking automatically, they both default to `off` whenever the working language changes to C or C`++`. This happens regardless of whether you or gdb selects the working language.

If you allow gdb to set the language automatically, it recognizes source files whose names end with `.c`, `.C`, or `.cc`, etc, and when gdb enters code compiled from one of these files, it sets the working language to C or C`++`. See Having gdb Infer the Source Language, for further details.