[{"id":3673408,"web_url":"http://patchwork.ozlabs.org/comment/3673408/","msgid":"","list_archive_url":null,"date":"2026-04-04T09:02:57","subject":"Re: [PATCH] libstdc++: Guard use of float16_t and bfloat16_t","submitter":{"id":4329,"url":"http://patchwork.ozlabs.org/api/people/4329/","name":"Jonathan Wakely","email":"jwakely.gcc@gmail.com"},"content":"OK, thanks\n\n(You'll need to add the PR number to the first line to get past the hooks)\n\nOn Sat, 4 Apr 2026, 09:35 Matthias Kretz, wrote:\n\n> The rest of this test is still relevant, thus only the (b)float16_t\n> tests are made optional rather than skipping the whole test via\n> dg-effective-target.\n>\n> libstdc++-v3/ChangeLog:\n>\n> PR libstdc++/124722\n> * testsuite/std/simd/traits_impl.cc: Add __STDCPP_FLOAT16_T__\n> and __STDCPP_BFLOAT16_T__ guards.\n>\n> Signed-off-by: Matthias Kretz \n> ---\n> libstdc++-v3/testsuite/std/simd/traits_impl.cc | 16 +++++++++++++++-\n> 1 file changed, 15 insertions(+), 1 deletion(-)\n>\n> diff --git a/libstdc++-v3/testsuite/std/simd/traits_impl.cc b/libstdc++-v3/\n> testsuite/std/simd/traits_impl.cc\n> index a264bd5f140..06bf6d5be25 100644\n> --- a/libstdc++-v3/testsuite/std/simd/traits_impl.cc\n> +++ b/libstdc++-v3/testsuite/std/simd/traits_impl.cc\n> @@ -9,7 +9,9 @@\n>\n> namespace simd = std::simd;\n>\n> +#ifdef __STDCPP_FLOAT16_T__\n> using std::float16_t;\n> +#endif\n> using std::float32_t;\n> using std::float64_t;\n>\n> @@ -17,7 +19,11 @@ namespace simd\n>\n> void test()\n> {\n> - template for (auto t : {float(), double(), float16_t(), float32_t(),\n> float64_t()})\n> + template for (auto t : {float(), double(),\n> +#ifdef __STDCPP_FLOAT16_T__\n> + float16_t(),\n> +#endif\n> + float32_t(), float64_t()})\n> {\n> using T = decltype(t);\n> static_assert(__vectorizable);\n> @@ -25,7 +31,9 @@ namespace simd\n>\n> static_assert(!__vectorizable);\n> static_assert(!__vectorizable);\n> +#ifdef __STDCPP_BFLOAT16_T__\n> static_assert(!__vectorizable);\n> +#endif\n>\n> template for (constexpr int N : {1, 2, 4, 8})\n> {\n> @@ -82,8 +90,10 @@ namespace simd\n> static_assert( __value_preserving_convertible_to);\n> static_assert(!__value_preserving_convertible_to);\n>\n> +#ifdef __STDCPP_FLOAT16_T__\n> static_assert(__explicitly_convertible_to);\n> static_assert(__explicitly_convertible_to);\n> +#endif\n>\n> static_assert(__constexpr_wrapper_like>);\n> static_assert(__constexpr_wrapper_like>);\n> @@ -95,7 +105,9 @@ namespace simd\n> static_assert(!__broadcast_constructible);\n>\n> static_assert(__broadcast_constructible), float>);\n> +#ifdef __STDCPP_FLOAT16_T__\n> static_assert(__broadcast_constructible),\n> std::float16_t>);\n> +#endif\n>\n>\n> static_assert(__higher_rank_than);\n> @@ -112,7 +124,9 @@ namespace simd\n> static_assert(__higher_rank_than);\n> static_assert(__higher_rank_than);\n>\n> +#ifdef __STDCPP_FLOAT16_T__\n> static_assert(__higher_rank_than);\n> +#endif\n> static_assert(__higher_rank_than);\n> static_assert(__higher_rank_than);\n> static_assert(__higher_rank_than);\n> --\n> ──────────────────────────────────────────────────────────────────────────\n> Dr. Matthias Kretz https://mattkretz.github.io\n> GSI Helmholtz Center for Heavy Ion Research https://gsi.de\n> std::simd\n> ──────────────────────────────────────────────────────────────────────────\n>\n>\n>\n>\n>","headers":{"Return-Path":"","X-Original-To":["incoming@patchwork.ozlabs.org","gcc-patches@gcc.gnu.org"],"Delivered-To":["patchwork-incoming@legolas.ozlabs.org","gcc-patches@gcc.gnu.org"],"Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256\n header.s=20251104 header.b=LklPHWUk;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org\n (client-ip=2620:52:6:3111::32; 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Sat, 04 Apr 2026\n 02:03:08 -0700 (PDT)","MIME-Version":"1.0","References":"<6327994.e9J7NaK4W3@vir-laptop>","In-Reply-To":"<6327994.e9J7NaK4W3@vir-laptop>","From":"Jonathan Wakely ","Date":"Sat, 4 Apr 2026 10:02:57 +0100","X-Gm-Features":"AQROBzAPZkg80fhFIlK1XT9v2-S0bc6tYD6gALI0XRDPuJaXOl-7s3n-8EIsREA","Message-ID":"\n ","Subject":"Re: [PATCH] libstdc++: Guard use of float16_t and bfloat16_t","To":"Matthias Kretz ","Cc":"\"libstdc++\" , gcc-patches ","Content-Type":"multipart/alternative; boundary=\"000000000000cb9f3b064e9eb3c9\"","X-BeenThere":"gcc-patches@gcc.gnu.org","X-Mailman-Version":"2.1.30","Precedence":"list","List-Id":"Gcc-patches mailing list ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"gcc-patches-bounces~incoming=patchwork.ozlabs.org@gcc.gnu.org"}}]