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1 /* AVR-GCC does not have real double datatype. Instead its double
2  * is equal to float, i.e. 32 bit value. If you need to communicate
3  * with other systems that use double in their .proto files, you
4  * need to do some conversion.
5  *
6  * These functions use bitwise operations to mangle floats into doubles
7  * and then store them in uint64_t datatype.
8  */
9 
10 #ifndef DOUBLE_CONVERSION
11 #define DOUBLE_CONVERSION
12 
13 #include <stdint.h>
14 
15 /* Convert native 4-byte float into a 8-byte double. */
16 extern uint64_t float_to_double(float value);
17 
18 /* Convert 8-byte double into native 4-byte float.
19  * Values are rounded to nearest, 0.5 away from zero.
20  * Overflowing values are converted to Inf or -Inf.
21  */
22 extern float double_to_float(uint64_t value);
23 
24 
25 #endif
26 
27