c++ - segmentation fault in programm with SIMD commands -

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what wrong here? when run program, says, segmentation fault (core dumped). have used simd commands.

float function ( point p1, point p2, int dim ) {       int k;       float result=0.0;       float *p3;       p3 = (float*) malloc (16);       k=dim%4;        __m128 *v_p1 = (__m128*)p1.coord;       __m128 *v_p2 = (__m128*)p2.coord;       __m128 *v_p3 = (__m128*)p3;        (int i=0; i<dim/4; i++){              *v_p3= _mm_sub_ps(*v_p1,*v_p2);       }       for(int i=0; i<dim; i++){              result+=p3[i];       }       return(result); }

any of simd _ps instructions going require 16 byte aligned data. can tell @ least p3 not aligned , seg fault if not use aligned data. can not run code myself if assign __m128 variables value should okay since should aligned:

  __m128 v_p1 = _mm_set_ps( ... ); // not sure of argument    __m128 v_p2 = _mm_set_ps( ... ); // not sure of argument    __m128 v_p3 = _mm_set_ps1(p3) ;

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