ClickHouse/libs/libcommon/include/common/preciseExp10.h

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#pragma once
/** exp10 from GNU libm fails to give precise result for integer arguments.
* For example, exp10(3) gives 1000.0000000000001
* despite the fact that 1000 is exactly representable in double and float.
* Better to always use implementation from MUSL.
*
* Note: the function names are different to avoid confusion with symbols from the system libm.
*/
#include <stdlib.h> /// for __THROW
// freebsd have no __THROW
#if !defined(__THROW)
#define __THROW
#endif
extern "C"
{
double preciseExp10(double x) __THROW;
double precisePow10(double x) __THROW;
float preciseExp10f(float x) __THROW;
float precisePow10f(float x) __THROW;
}