lib/libc/min: Introduce simple math.h

/*

 * Copyright (c) 2019 Linaro Limited.

 *

 * SPDX-License-Identifier: Apache-2.0

 */

#ifndef ZEPHYR_LIB_LIBC_MINIMAL_INCLUDE_MATH_H_

#define ZEPHYR_LIB_LIBC_MINIMAL_INCLUDE_MATH_H_

#ifdef __cplusplus

extern "C" {

#endif

#if !defined(FLT_EVAL_METHOD) && defined(__FLT_EVAL_METHOD__)

#define FLT_EVAL_METHOD __FLT_EVAL_METHOD__

#endif

#if defined FLT_EVAL_METHOD

	#if FLT_EVAL_METHOD == 0

		typedef float  float_t;

		typedef double double_t;

	#elif FLT_EVAL_METHOD == 1

		typedef double float_t;

		typedef double double_t;

	#elif FLT_EVAL_METHOD == 2

		typedef long double float_t;

		typedef long double double_t;

	#else

		/* Implementation-defined.  Assume float_t and double_t have

		 * already been defined */

	#endif

#else

	typedef float  float_t;

	typedef double double_t;

#endif

#ifdef __cplusplus

}

#endif

#endif /* ZEPHYR_LIB_LIBC_MINIMAL_INCLUDE_MATH_H_ */