Nicolas Setton wrote:
In order to make the transition easier, and to allow time for other tools (mainly gdb) to take advantage of these improvements at their own schedule, we would like to introduce a command-line switch (- gdwarf+), which will trigger the use of the GNAT vendor extension to DWARF.
I doubt that anyone outside Adacore cares much about how GNAT emits debug info. However, this bit caught my eye.
Any properly written dwarf reader will ignore attributes it doesn't understand, and hence in theory there should be no need for a -gdwarf-2+ option. You can just emit the new info by default and everything should work.
If you are proposing -gdwarf-2+ because you want to have support for both the old and new Ada debug info, then I think that is a misuse of the debug+ convention. You aren't really adding extensions. You are just changing from stabs hacks to proper dwarf info. Also, having the -gdwarf-2+ option may confuse people into thinking that they need it for C++ (which is where the + originally came from).
Not having both means that gdb patches need to get installed first, then the gcc patches, and then you document that gcc version X requires gdb version Y. Ordinarily this shouldn't be a problem, but I realize that historically gdb support for Ada hasn't been as good as it should be. If we really need both old and new formats, I'd suggest a -f option first, maybe something like -fada-stabs-encodings to get the old format.
-- Jim Wilson, GNU Tools Support, http://www.specifix.com
