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#if defined(__GNUC__) && (__GNUC__ >= 5)
#include "uint16.h"
int imult16( int16 a, int16 b, int16* c) { return !__builtin_mul_overflow(a,b,c); }
#else
#include "safemult.h"
int imult16(int16 a,int16 b,int16* c) {
int32 x=(int32)a*b;
if ((int16)x != x) return 0;
*c=x;
return 1;
}
#endif
#ifdef UNITTEST
#include <assert.h>
int main() {
int16 a;
assert(imult16(4,10000,&a)==0);
assert(imult16(-4,10000,&a)==0);
assert(imult16(5,10,&a)==1 && a==50);
assert(imult16(-3,10000,&a)==1 && a==-30000);
return 0;
}
#endif