1 /* 2 * Copyright 2023, Haiku Inc. All Rights Reserved. 3 * Distributed under the terms of the MIT License. 4 */ 5 #ifndef _KERNEL_MATH_H 6 #define _KERNEL_MATH_H 7 8 /* 9 When building the kernel, the bootloader or kernel add-ons, the Haiku build system passes the 10 `-ffreestanding` argument to GCC, in order to make sure that only the C++ language features can 11 be used that do not require the C/C++ standard library. 12 The Haiku kernel and boot loaders include part of the standard library in the kernel/boot 13 loader. It uses the C/C++ standard library headers (like this one) to expose the 14 functions/features that are available in the kernel/boot loader. 15 16 If we are building for the kernel or the boot loader, the logic below will tell GCC's C++ 17 headers to include the underlying posix headers, so that the kernel, the boot loader and kernel 18 add-ons can link to the symbols defined in them. 19 20 When we are NOT building for the kernel or the boot loader, we fall back to GCC's default 21 behaviour. 22 */ 23 24 #if (defined(_KERNEL_MODE) || defined(_BOOT_MODE)) && !defined(_GLIBCXX_INCLUDE_NEXT_C_HEADERS) 25 # define _GLIBCXX_INCLUDE_NEXT_C_HEADERS 26 # include_next <math.h> 27 # undef _GLIBCXX_INCLUDE_NEXT_C_HEADERS 28 #else 29 # include_next <math.h> 30 #endif 31 32 33 #endif // _KERNEL_MATH_H 34