Re: GDB does not recognize cxx extension?

["Christian Biesinger via gdb" <gdb@sourceware.org>]

On Sun, Sep 29, 2019 at 12:17 AM Jeffrey Walton <noloader@gmail.com> wrote:
>
> On Sun, Sep 29, 2019 at 1:09 AM Christian Biesinger
> <cbiesinger@google.com> wrote:
> >
> > On Sun, Sep 29, 2019 at 12:01 AM Jeffrey Walton <noloader@gmail.com> wrote:
> > > I've got a C++ program built from a source called pem_test.cxx. I'm
> > > having trouble getting GDB to accept it. Autocomplete does not work:
> > >
> > >     (gdb) b pem_<TAB>
> > >     pem_common.cpp  pem_common.h    pem_read.cpp    pem_write.cpp
> >
> > GDB gets the list of files from the debug data in the binary, not from
> > the current directory. Are you sure you compiled pem_test.cxx into the
> > binary?
>
> Yes. A 'b main' stops in pem_test.cxx.
>
> The recipe to build pem_test.cxx is at
> https://github.com/noloader/cryptopp-pem/blob/master/pem_create_keys.sh#L42

So, GDB does know that cxx is an extension for C++:
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=blob;f=gdb/c-lang.c;h=57592dfbce0f8822fa3ca3d68ed520b4124a0c5d;hb=612aac65e690387c963c34a31dd1fb138d88a45c#l1032

And .cxx does work for me:
Reading symbols from ./test...
(gdb) break test.cxx:2
Breakpoint 1 at 0x1129: file test.cxx, line 2.
(gdb) r
Starting program: /tmp/test

Breakpoint 1, main () at test.cxx:2
2   return 42;
(gdb) b test<TAB>
std::__atomic0::atomic_flag::test_and_set(std::memory_order)           test.cxx

There must be something odd about your build setup, but I don't know
what it is. For testing purposes, if you build the cxx as part of your
static library, does it work?

Christian