[Bug testsuite/116143] [15 regression] gcc.dg/plugin/diagnostic-* test fails intermittently

[dmalcolm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116143

--- Comment #5 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
(In reply to David Malcolm from comment #1)
[...snip...]
> My guess is that nothing is using class simple_diagnostic_path in cc1, and
> thus the code for simple_diagnostic_path is being dropped by the linker, so
> it's not available to the plugin.

It's used by a selftest in simple-diagnostic-path.cc, but that's only enabled
if
  #if CHECKING_P
so maybe this is failing on release builds and passing on debug builds???

FWIW I've seen a couple of patches in progress that add "real" uses of the
class to the middle-end (e.g. Qing's "[RFC][PATCH v1] Provide more contexts for
-Warray-bounds warning messages "
https://gcc.gnu.org/pipermail/gcc-patches/2024-July/656199.html )