[libc-commits] [libc] [libc] Fix generated float128 header for aarch64 target. (PR #78017)

[Nick Desaulniers via libc-commits]

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@@ -0,0 +1,31 @@
+//===-- Definition of float128 type ---------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef __LLVM_LIBC_TYPES_FLOAT128_H__
+#define __LLVM_LIBC_TYPES_FLOAT128_H__
+
+#include <include/llvm-libc-macros/float-macros.h> // LDBL_MANT_DIG
+
+// TODO: https://github.com/llvm/llvm-project/issues/80195
+//   Check _Float128 C23 type detection again when clang supports it.
+#if defined(__STDC_IEC_60559_BFP__) && !defined(__clang__)
+// Use _Float128 C23 type.
+#define LIBC_COMPILER_HAS_C23_FLOAT128
+typedef _Float128 float128;
+#elif defined(__FLOAT128__)
+// Use __float128 type.
+// clang uses __FLOAT128__ macro to notify the availability of __float128 type:
+//   https://reviews.llvm.org/D15120
+#define LIBC_COMPILER_HAS_FLOAT128_EXTENSION
+typedef __float128 float128;
+#elif (LDBL_MANT_DIG == 113)
+// Use long double.
+typedef long double float128;
+#endif
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nickdesaulniers wrote:

SGTM; we'll hopefully be revisiting this block of preprocessor checks when compilers improve their support. Let's get the build back to green.

https://github.com/llvm/llvm-project/pull/78017