https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81167
--- Comment #3 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
The issue is that a diagnostic is passing NULL to a %qH (which was a %qT).
%T handles NULL gracefully by printing the empty string,
whereas %H/%I fail with an assertion failure.
Happens here:
#8 0x000000000081469e in joust(z_candidate*, z_candidate*, bool, int) [clone
.part.38] ()
at ../../src/gcc/cp/call.c:10075
10075 && warning (OPT_Wconversion, " for conversion from %qH
to %qI",
10076 source, w->second_conv->type))
(gdb) p source
$2 = (tree_node *) 0x0
(gdb) p w->second_conv->type
$3 = <record_type 0x7ffff0072690 tuple>
