Bug 4083 – Exception-related code from nothrow destructor

This can be related to bug 4082. This program works correctly with dmd 2.043, but the resulting asm contains code for the management of exceptions even if the destructor of the struct Foo is nothrow (I am not sure if this situation can be improved): struct Foo { nothrow ~this() {} } void main() { Foo f; goto NEXT; NEXT:; } __Dmain L0: push EBP mov EBP,ESP mov EDX,FS:__except_list push 0FFFFFFFFh push offset __Dmain[061h] push EDX mov FS:__except_list,ESP sub ESP,8 push EAX push EBX push ESI push EDI mov dword ptr -4[EBP],0 mov dword ptr -4[EBP],0FFFFFFFFh lea ECX,-0Ch[EBP] push 0FFFFFFFFh push ECX push offset FLAT:_DATA call near ptr __d_local_unwind2 add ESP,0Ch push offset __Dmain[04Eh] mov dword ptr -4[EBP],0FFFFFFFFh ret mov ECX,-0Ch[EBP] xor EAX,EAX mov FS:__except_list,ECX pop EDI pop ESI pop EBX mov ESP,EBP pop EBP ret mov EAX,offset FLAT:_DATA jmp near ptr __d_framehandler

Now on DMD 2.079 nothrow is optimized well, so it was fixed in the meantime: 000000000000000 <_Dmain>: 0: 55 push %rbp 1: 48 8b ec mov %rsp,%rbp 4: 48 83 ec 10 sub $0x10,%rsp 8: 48 8d 45 f8 lea -0x8(%rbp),%rax c: c6 00 00 movb $0x0,(%rax) f: b9 03 00 00 00 mov $0x3,%ecx 14: 89 4d fc mov %ecx,-0x4(%rbp) 17: 48 89 c7 mov %rax,%rdi 1a: e8 00 00 00 00 callq 1f <_Dmain+0x1f> 1f: 83 7d fc 03 cmpl $0x3,-0x4(%rbp) 23: 74 02 je 27 <_Dmain+0x27> 25: c9 leaveq 26: c3 retq 27: 31 c0 xor %eax,%eax 29: c9 leaveq 2a: c3 retq