[lldb-dev] test system, when using clang, flags

[Reid Kleckner]

On Wed, Jul 9, 2014 at 9:04 AM, Todd Fiala <tfiala at google.com> wrote:

> Hey all,
>
> When running lldb tests with clang, on non-Apple platforms, we really need
> this flag set:
> -fstandalone-debug
>

We think this is a bug in LLDB, and would *really* like to see it fixed.
 gdb works fine without this flag, and it *drastically* reduces the amount
of debug info stored in object files.  My understanding is that the debug
info that LLDB needs is there, but it's in a different compilation unit.

Usually the missing information is type information about a class with a
vtable where the first virtual method (aka the key function) is defined in
a different TU.  That TU will emit the vtable and all type information for
that class.

That said, it's fine if LLDB has to add the flag as a short-term way to
stabilize the test suite.  I just want to make sure we're on the same page
here: this is probably an LLDB bug, not a Clang bug.


> It addresses issues where we end up missing complete debuginfo without it
> in some cases.  That ends up breaking the debugger's ability to perform
> some operations.  So, we're going to want that flag set when running tests
> on a host other than MacOSX.
>
> We have a couple ways I suppose we can go about that: modify all the test
> build files to check if CC/CXX is clang, and add the symbol if so.  Or we
> can do something in the test framework build functions that tries to figure
> that out, and adds it if appropriate.
>
> Any preferences on the way to handle this?
> --
> Todd Fiala | Software Engineer |  tfiala at google.com |  650-943-3180
>
> _______________________________________________
> lldb-dev mailing list
> lldb-dev at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/lldb-dev
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/lldb-dev/attachments/20140709/0f74d121/attachment.html>