Gdb/Automatically
15.1.3 Having GDB Infer the Source Language
To have GDB set the working language automatically, use
‘set language local’ or ‘set language auto’. GDB
then infers the working language. That is, when your program stops in a
frame (usually by encountering a breakpoint), GDB sets the
working language to the language recorded for the function in that
frame. If the language for a frame is unknown (that is, if the function
or block corresponding to the frame was defined in a source file that
does not have a recognized extension), the current working language is
not changed, and GDB issues a warning.
This may not seem necessary for most programs, which are written
entirely in one source language. However, program modules and libraries
written in one source language can be used by a main program written in
a different source language. Using ‘set language auto’ in this
case frees you from having to set the working language manually.