Re: [rfc] Be in language c more c++ compatible

[Matt Rice <ratmice at gmail dot com>]

On Fri, Jul 15, 2011 at 12:19 PM, Jan Kratochvil
<jan.kratochvil@redhat.com> wrote:
> Hi,
>
> I always see some terrible C++ GDB bug so I fix in some hours and then find out
> it works in GDB when one has `set language c++'. ?This usually happens with
> artificial testcases like the one today:
> ? ? ? ?http://sourceware.org/ml/gdb-patches/2011-07/msg00387.html

was curious what it did with the attached objc++ version.

which isn't really a supported language by any means.
gdb considers it to be 'minimal'/doesn't recognize the CU language in
the debuginfo.  and it is difficult to say how meaningful it would be
if it did.
I imagine gdb wants DW_TAG_partial_unit/DW_AT_language when
switching between c++/objective-c functions, I hadn't been able to
coax this out of gcc

anyhow the last line was a bit suprising.

gcc -g -o objcxx objc++.mm -lobjc

GNU gdb (GDB) Fedora (7.2-51.fc14)
(gdb) set language c++
(gdb) whatis C::t
No symbol "C" in current context.
(gdb) set language objective-c
(gdb) whatis C::t
No symbol "C" in current context.
(gdb) break main
Breakpoint 1 at 0x400808: file objc++.mm, line 47.
(gdb) r
Breakpoint 1, main () at objc++.mm:47
47	  Foo *foo = [[Foo alloc] init];
Warning: the current language does not match this frame.
(gdb) whatis C::t
type = t
(gdb) show language
The current source language is "objective-c".
Warning: the current language does not match this frame.
(gdb) set language c++
(gdb) whatis C::t
A syntax error in expression, near `'.

Attachment: objc++.mm
Description: Text document