-isystem and C++ headers

[Daniel Jacobowitz]

On Tue, May 11, 2004 at 07:24:05PM -0400, Daniel Jacobowitz wrote:
> c-opts.c says this:
> 
>     case OPT_isystem:
>       add_path (xstrdup (arg), SYSTEM, 0);
>       break;
> 
> Is there a particular reason the third argument, cxx_aware, is not set? 
> This means that anything included via -isystem will be marked with extern
> "C" by g++.  This breaks the GDB testsuite in a combined tree, because all
> of libstdc++'s headers get marked as "system" headers.  This isn't new, I
> don't think; I usually run my GDB testsuites using an installed compiler
> instead because I've had such a hard time getting combined trees to search
> in the tree instead of the install dir.
> 
> The -isystem comes from DejaGNU, and has for a long time: see proc
> g++_include_flags in libgloss.exp.  DejaGNU should probably be updated to
> invoke scripts/testsuite_flags instead.  It looks like this aspect of
> -isystem hasn't changed since at least 3.2, but I'm still not sure it's
> right.

Question stands, but here's the explanation as to why I never saw it
before: dejagnu in src has been changed to use -I.  Dejagnu upstream
uses -isystem.

-- 
Daniel Jacobowitz