On Fri, 20 Dec 2019 at 21:28, Marek Polacek <[email protected]> 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.
>
> Hi,
The new test fails on aarch64:
g++.dg/cpp0x/initlist118.C -std=c++14 (internal compiler error)
g++.dg/cpp0x/initlist118.C -std=c++14 (test for excess errors)
g++.dg/cpp0x/initlist118.C -std=c++17 (internal compiler error)
g++.dg/cpp0x/initlist118.C -std=c++17 (test for excess errors)
g++.dg/cpp0x/initlist118.C -std=c++2a (internal compiler error)
g++.dg/cpp0x/initlist118.C -std=c++2a (test for excess errors)
The log says:
during RTL pass: reload
/gcc/testsuite/g++.dg/cpp0x/initlist118.C: In function 'array<__vector(4)
float,
4> transpose(array<__vector(4) float, 4>)':
/gcc/testsuite/g++.dg/cpp0x/initlist118.C:25:1: internal compiler error:
maximum
number of generated reload insns per insn achieved (90)
0xd7686f lra_constraints(bool)
/gcc/lra-constraints.c:4946
0xd5d834 lra(_IO_FILE*)
/gcc/lra.c:2437
0xd10209 do_reload
/gcc/ira.c:5526
0xd10209 execute
/gcc/ira.c:5712
Please submit a full bug report,
Christophe
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));
> diff --git gcc/testsuite/g++.dg/cpp0x/initlist118.C
> gcc/testsuite/g++.dg/cpp0x/initlist118.C
> new file mode 100644
> index 00000000000..2e1b96953e3
> --- /dev/null
> +++ gcc/testsuite/g++.dg/cpp0x/initlist118.C
> @@ -0,0 +1,25 @@
> +// PR c++/92745 - bogus error when initializing array of vectors.
> +// { dg-do compile { target c++11 } }
> +
> +template <typename a, int b> struct c {
> + typedef a d[b];
> +};
> +
> +template <typename a, int b> struct array {
> + typename c<a, b>::d e;
> + a operator[](long);
> +};
> +
> +template<class T>
> +using vec4_t __attribute__((vector_size(4*sizeof(T)))) = float;
> +
> +array<vec4_t<float>, 4>
> +transpose(array<vec4_t<float>, 4> col)
> +{
> + array<vec4_t<float>, 4>
> + ret{vec4_t<float>{col[0][0], col[1][0], col[2][0], col[3][0]},
> + vec4_t<float>{col[0][1], col[1][1], col[2][1], col[3][1]},
> + vec4_t<float>{col[0][2], col[1][2], col[2][2], col[3][2]},
> + vec4_t<float>{col[0][3], col[1][3], col[2][3], col[3][3]}};
> + return ret;
> +}
>
>
