Unambiguously specifying source locations

[Felix Lee]

>  [libfoo.so.2][foo-1.cc:foo_func:75][bar-1.h:inline_one:33]\
>    [bar-1.h:inline_two:36]

One thing I'm not clear about, you're mixing source locators with
object locators.  Is it really a path?  Maybe it should be
an arbitrary qualifier list instead?  Like
    foofunc[obj libfoo.so]
    foofunc[src foo.h in foo1.cc]
the first would be all foofunc in libfoo.so. the second would be
all foofunc the compiler generates from foo.cc/foo.h.  and
perhaps let the user combine qualifiers with boolean operators.
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