On Mon, Mar 26, 2018 at 5:19 AM, Paolo Carlini <paolo.carl...@oracle.com> wrote: > On 23/03/2018 13:39, Jason Merrill wrote: >> On Fri, Mar 23, 2018 at 6:13 AM, Paolo Carlini <paolo.carl...@oracle.com> >> wrote: >>> >>> On 22/03/2018 23:26, Jason Merrill wrote: >>>> >>>> On Thu, Mar 22, 2018 at 5:39 PM, Paolo Carlini >>>> <paolo.carl...@oracle.com> >>>> wrote: >>>>> >>>>> ... with patch ;) >>>>> >>>>> If you are curious where the heck that INDIRECT_REF is coming from, is >>>>> coming from the gimplifier, cp_gimpliify_expr, via build_vec_init. >>>>> Grrr. >>>> >>>> Hmm, maybe build_vec_init should call itself directly rather than via >>>> build_aggr_init in the case of multidimensional arrays. >>> >>> Yes, arranging things like that seems doable. However, yesterday, while >>> fiddling with the idea and instrumenting the code with some gcc_asserts, >>> I >>> noticed that we have yet another tree code to handle, TARGET_EXPR, as in >>> lines #41, #47, #56 of ext/complit12.C, and in that case build_aggr_init >>> is >>> simply called by check_initializer via build_aggr_init_full_exprs, the >>> "normal" path. Well, unless we want to adjust/reject complit12.C too, >>> which >>> clang rejects, in fact with errors on lines #19 and #29 too. The below >>> passes testing. >> >> I think I'd like to allow TARGET_EXPR here, with a comment about >> compound literals, but avoid INDIRECT_REF with that build_vec_init >> change. > > I see. Having run the full testsuite a number of times with additional > gcc_asserts, I'm very confident that something as simple as the below is > fine, at least as far as the testsuite + variants of lambda-array.C is > concerned. In it I'm also proposing a gcc_assert verifying that the very > idea of not using any diagnostic conditional makes sense for the internally > generated INDIRECT_REFs: in the existing build_aggr_init if the types were > different from_array would be zero and, for INDIRECT_REF as init, the > condition true.
Your build_aggr_init change is OK, but I had in mind something more general in build_vec_init:
diff --git a/gcc/cp/init.c b/gcc/cp/init.c index ff52c42c1ad..d689390d117 100644 --- a/gcc/cp/init.c +++ b/gcc/cp/init.c @@ -4367,7 +4367,10 @@ build_vec_init (tree base, tree maxindex, tree init, else from = NULL_TREE; - if (from_array == 2) + if (TREE_CODE (type) == ARRAY_TYPE) + elt_init = build_vec_init (to, NULL_TREE, from, /*val_init*/false, + from_array, complain); + else if (from_array == 2) elt_init = cp_build_modify_expr (input_location, to, NOP_EXPR, from, complain); else if (type_build_ctor_call (type))
