Even with pr97027 resolved -Wstringop-overflow is not issued consistently (on all targets) for buffer overflow when storing a larger compound literal into a smaller buffer.  The test case below is diagnosed by -Warray-bounds which is only enabled with -Wall and at -O2, but not by -Wstringop-overflow (which is enabled by default).  Ideally the bug should be diagnosed even at -O0.

$ cat a.c && gcc -O2 -S -fdump-tree-strlen=/dev/stdout a.c 
typedef struct A { char a[4]; } A;

extern char a[2];

void f (void)
{
  *(A*)a = (A){ 1, 2, 3, 4 };   // missing warning
}

typedef struct B { int a[2]; } B;
  
void g (void)
{
  *(B*)a = (B){ 1, 2 };   // missing warning
}

;; Function f (f, funcdef_no=0, decl_uid=3910, cgraph_uid=1, symbol_order=0)

;; 1 loops found
;;
;; Loop 0
;;  header 0, latch 1
;;  depth 0, outer -1
;;  nodes: 0 1 2
;; 2 succs { 1 }
void f ()
{
  <bb 2> [local count: 1073741824]:
  MEM[(struct A *)&a].a[0] = 1;
  MEM[(struct A *)&a].a[1] = 2;
  MEM[(struct A *)&a].a[2] = 3;
  MEM[(struct A *)&a].a[3] = 4;
  return;

}



;; Function g (g, funcdef_no=1, decl_uid=3917, cgraph_uid=2, symbol_order=1)

;; 1 loops found
;;
;; Loop 0
;;  header 0, latch 1
;;  depth 0, outer -1
;;  nodes: 0 1 2
;; 2 succs { 1 }
void g ()
{
  <bb 2> [local count: 1073741824]:
  MEM[(struct B *)&a].a[0] = 1;
  MEM[(struct B *)&a].a[1] = 2;
  return;

}