On Fri, Dec 20, 2019, 6:22 PM Marek Polacek <[email protected]> wrote:
> On Fri, Dec 20, 2019 at 05:56:39PM -0500, Jason Merrill wrote:
> > On 12/20/19 3:27 PM, Marek Polacek wrote:
> > > In r268428 I changed reshape_init_r in such a way that when it sees
> > > a nested { } in a CONSTRUCTOR with missing braces, it just returns
> > > the initializer:
> > > + else if (COMPOUND_LITERAL_P (stripped_init)
> > > ...
> > > + ++d->cur;
> > > + gcc_assert (!BRACE_ENCLOSED_INITIALIZER_P (stripped_init));
> > > + return init;
> > >
> > > But as this test shows, that's incorrect: if TYPE is an array, we need
> > > to proceed to reshape_init_array_1 which will iterate over the array
> > > initializers:
> > > 6006 /* Loop until there are no more initializers. */
> > > 6007 for (index = 0;
> > > 6008 d->cur != d->end && (!sized_array_p || index <=
> max_index_cst);
> > > 6009 ++index)
> > > 6010 {
> > > and update d.cur accordingly. In other words, when reshape_init gets
> > >
> > > {{col[0][0], col[1][0], col[2][0], col[3][0]},
> > > {col[0][1], col[1][1], col[2][1], col[3][1]},
> > > {col[0][2], col[1][2], col[2][2], col[3][2]},
> > > {col[0][3], col[1][3], col[2][3], col[3][3]}}
> > >
> > > we recurse on the first element:
> > > {col[0][0], col[1][0], col[2][0], col[3][0]}
> > > and we can't just move d.cur to point to
> > > {col[0][1], col[1][1], col[2][1], col[3][1]}
> > > and return; we need to iterate, so that d.cur ends up being properly
> > > updated, and after all initializers have been seen, points to d.end.
> > > Currently we skip the loop, wherefore we hit this:
> > >
> > > 6502 /* Make sure all the element of the constructor were used.
> Otherwise,
> > > 6503 issue an error about exceeding initializers. */
> > > 6504 if (d.cur != d.end)
> > > 6505 {
> > > 6506 if (complain & tf_error)
> > > 6507 error ("too many initializers for %qT", type);
> > > 6508 return error_mark_node;
> > > 6509 }
> > >
> > > Bootstrapped/regtested on x86_64-linux, built cmcstl2, ok for trunk
> > > and branches?
> > >
> > > 2019-12-20 Marek Polacek <[email protected]>
> > >
> > > PR c++/92745 - bogus error when initializing array of vectors.
> > > * decl.c (reshape_init_r): For a nested compound literal, do
> > > call reshape_init_{class,array,vector}.
> > >
> > > * g++.dg/cpp0x/initlist118.C: New test.
> > >
> > > diff --git gcc/cp/decl.c gcc/cp/decl.c
> > > index 7d4c947fb58..c15cbfa3bd3 100644
> > > --- gcc/cp/decl.c
> > > +++ gcc/cp/decl.c
> > > @@ -6399,14 +6399,13 @@ reshape_init_r (tree type, reshape_iter *d,
> bool first_initializer_p,
> > > by the front end. Here we have e.g. {.__pfn=0B,
> .__delta=0},
> > > which is missing outermost braces. We should warn below,
> and
> > > one of the routines below will wrap it in additional { }.
> */;
> > > - /* For a nested compound literal, there is no need to reshape
> since
> > > - we called reshape_init in finish_compound_literal, before
> calling
> > > - digest_init. */
> > > - else if (COMPOUND_LITERAL_P (stripped_init)
> > > - /* Similarly, a CONSTRUCTOR of the target's type is a
> > > - previously digested initializer. */
> > > - || same_type_ignoring_top_level_qualifiers_p (type,
> > > -
> init_type))
> > > + /* For a nested compound literal, proceed to specialized
> routines,
> > > + to handle initialization of arrays and similar. */
> > > + else if (COMPOUND_LITERAL_P (stripped_init))
> > > + gcc_assert (!BRACE_ENCLOSED_INITIALIZER_P (stripped_init));
> > > + /* A CONSTRUCTOR of the target's type is a previously
> > > + digested initializer. */
> > > + else if (same_type_ignoring_top_level_qualifiers_p (type,
> init_type))
> > > {
> > > ++d->cur;
> > > gcc_assert (!BRACE_ENCLOSED_INITIALIZER_P (stripped_init));
> >
> > Incidentally, asserting !BRACE_ENCLOSED_INITIALIZER_P seems pretty
> > pointless, since that checks for init_list_type_node, and a compound
> literal
> > won't have that type, nor will we see that type if we just checked that
> it's
> > something else.
>
> True, would an obvious patch to remove that assert be OK?
>
Yes.
--
> Marek Polacek • Red Hat, Inc. • 300 A St, Boston, MA
>
>
