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

[Ed Maste]

On 14 July 2014 15:03,  <jingham at apple.com> wrote:
> I haven't kept track of clang's debug reduction flags.  There used to be an -funused-types or -funused-declarations or something like that that covered not emitting type information declarations (originally in gcc it was just types, then it was made into all declarations.)

-fstandalone-debug was introduced last January in r198655, and
replaced the previous flag:

    Implement a new -fstandalone-debug option. rdar://problem/15685848
    It controls everything that -flimit-debug-info used to, plus the
    vtable type optimization. The old -fno-limit-debug-info option is now an
    alias to -fstandalone-debug and vice versa.

    Standalone is the default on Darwin until dtrace is updated to work with
    non-standalone debug info (rdar://problem/15758808).

I'm not aware of any more granular control.  On Darwin and FreeBSD
-fstandalone-debug is the default and everything is emitted.  On Linux
-fno-standalone-debug is the default, and as much as possible is
omitted.

To the original point, I don't think this has much effect on the
testsuite -- there's a decent correlation between Linux and FreeBSD
wrt XFAIL tests, with opposite defaults for the flag.  It's the
real-life problems with -fno-standalone-debug that I'm actually
interested in, but we (FreeBSD) currently won't encounter them with
the default options.