Re: [RFA] Add new language: "unsupported"

[Elena Zannoni <ezannoni at redhat dot com>]

Daniel Berlin writes:
 > 
 > On Tuesday, May 6, 2003, at 09:42  PM, Joel Brobecker wrote:
 > 
 > > As promised to Elena, this is a followup on:
 > >
 > >     http://sources.redhat.com/ml/gdb-patches/2003-04/msg00209.html
 > >
 > > Basically, I added a new "unsupported" language which support is
 > > minimalistic (identical to what we do with the "asm" language).
 > > I didn't fancy "partial":
 > >
 > >         (gdb) show lang
 > >         Current language:  auto; currently partial
 > >
 > > I felt like it could confuse the user to think that "partial" is the
 > > name of a real language :-). But I'm not such a big fan of 
 > > "unsupported"
 > > either, so all suggestions are welcome.
 > >
 > > This new language will first be used by the dwarf2 reader, for objects
 > > which language is currently not supported. What it does, at the moment,
 > > is use the "unknown" language, which makes a lot of the GDB commands
 > > fall flat. Like so, when debugging an Ada program:
 > >
 > >     (gdb) list foo.adb:1
 > >     internal error - unimplemented function 
 > > unk_lang_create_fundamental_type called.
 > >     (gdb) quit
 > >
 > > With the attached patch, and also the little patch to dwarf2read.c
 > > (attached too, will be submitted later, after this one is agreed on),
 > > GDB behaves in a much more friendly way:
 > >
 > >     (gdb) list foo.adb:1
 > >     1       procedure Foo is
 > >     2          A : Integer := 1;
 > >     3       begin
 > >     4          A := A + 1;
 > >     5       end Foo;
 > >     (gdb) b foo.adb:4
 > >     Breakpoint 1 at 0x8049769: file foo.adb, line 4.
 > >     (gdb) run
 > >     Starting program: /lek.a/brobecke/ada_example/foo
 > >
 > >     Breakpoint 1, _ada_foo () at foo.adb:4
 > >     4          A := A + 1;
 > >     Current language:  auto; currently unsupported
 > >     (gdb) p a
 > >     $1 = 1
 > 
 > 
 > 
 > It should probably warn (I guess it has to be in the reader, since we 
 > have no hook for when you switch to a language, right?) when it is 
 > switching to the unsupported language.
 > 
 > Something like "Warning: The current language is unsupported by GDB. 
 > Name lookups and printouts may not look like what you expect as a 
 > result".
 > 
 > That way, nobody files bugs because the unsupported language does what 
 > C would do, when they expect what <insert other language here> would do.

that's not a bad idea, actually. This must be the lawyer talking :-)