| /* Verify that NRV optimizations are prohibited when the LHS is an |
| indirect reference to something that may be call-clobbered. */ |
| /* { dg-do compile } */ |
| /* { dg-options "-O -fdump-tree-optimized" } */ |
| |
| typedef struct { int x[20]; void *y; } S; |
| S nrv_candidate (void); |
| void use_result (S); |
| void make_escape (S *); |
| S global_S; |
| void foo (void) |
| { |
| S *result; |
| S local_S; |
| |
| /* We can't perform return slot optimization because global_S is |
| global and may be clobbered by nrv_candidate. */ |
| result = &global_S; |
| *result = nrv_candidate (); |
| use_result (*result); |
| |
| /* We can't perform return slot optimization because local_S is |
| call_clobbered (its address escapes prior to invoking |
| nrv_candidate). */ |
| make_escape (&local_S); |
| result = &local_S; |
| *result = nrv_candidate (); |
| use_result (*result); |
| } |
| |
| /* { dg-final { scan-tree-dump-times "return slot optimization" 0 "optimized" } } */ |
| /* { dg-final { cleanup-tree-dump "optimized" } } */ |
| |