pass by value bug in msvc

repro.cpp

//this repro mangles the value of v.y in the pass_and_log function
//prints           0.20000 0.00000
//should print     0.20000 0.10000

//compiler: Microsoft (R) C/C++ Optimizing Compiler Version 19.29.30139 for x64 (VS 2019 latest as of 2/1/22)
//compile command: cl /O2 /Ob1 repro.cpp

#include <cstdio>
 
struct vec2 { float x; float y; };
 
void pass_and_log(vec2 v) { printf("%f %f\n", v.x, v.y); } //prints y = 0.0f
 
void bar(vec2 v, int *i) { *i = 2; }
 
void foo(int *i)
{
  vec2 v = {0.1f,0.1f};
  bar(v, i);
  v.x = 0.2f;
  for(size_t j = 0; j < 2; j++)
    pass_and_log(v);
}
 
int main()
{
  int i;
  foo(&i);
  return 0;
}