[Bug tree-optimization/109543] Avoid using BLKmode for unions with a non-BLKmode member when possible

[avieira at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109543

--- Comment #3 from avieira at gcc dot gnu.org ---
Err that should be 'double d[4];' so:
typedef struct 
{
    float __attribute__ ((vector_size(16))) v[2];
} STRUCT;

#ifdef GOOD
typedef STRUCT TYPE;
#else
typedef union
{
    STRUCT s;
    double d[4];
} TYPE;
#endif