fix optional pointer to size zero struct

src/codegen.cpp

@@ -4983,7 +4983,7 @@ static LLVMValueRef ir_render_unwrap_err_payload(CodeGen *g, IrExecutable *execu
     }
 }
 
-static LLVMValueRef ir_render_maybe_wrap(CodeGen *g, IrExecutable *executable, IrInstructionOptionalWrap *instruction) {
+static LLVMValueRef ir_render_optional_wrap(CodeGen *g, IrExecutable *executable, IrInstructionOptionalWrap *instruction) {
     ZigType *wanted_type = instruction->base.value.type;
 
     assert(wanted_type->id == ZigTypeIdOptional);
@@ -4991,11 +4991,20 @@ static LLVMValueRef ir_render_maybe_wrap(CodeGen *g, IrExecutable *executable, I
     ZigType *child_type = wanted_type->data.maybe.child_type;
 
     if (!type_has_bits(child_type)) {
-        return LLVMConstInt(LLVMInt1Type(), 1, false);
+        LLVMValueRef result = LLVMConstAllOnes(LLVMInt1Type());
+        if (instruction->result_loc != nullptr) {
+            LLVMValueRef result_loc = ir_llvm_value(g, instruction->result_loc);
+            gen_store_untyped(g, result, result_loc, 0, false);
+        }
+        return result;
     }
 
     LLVMValueRef payload_val = ir_llvm_value(g, instruction->operand);
     if (!handle_is_ptr(wanted_type)) {
+        if (instruction->result_loc != nullptr) {
+            LLVMValueRef result_loc = ir_llvm_value(g, instruction->result_loc);
+            gen_store_untyped(g, payload_val, result_loc, 0, false);
+        }
         return payload_val;
     }
 
@@ -5666,7 +5675,7 @@ static LLVMValueRef ir_render_instruction(CodeGen *g, IrExecutable *executable,
         case IrInstructionIdUnwrapErrPayload:
             return ir_render_unwrap_err_payload(g, executable, (IrInstructionUnwrapErrPayload *)instruction);
         case IrInstructionIdOptionalWrap:
-            return ir_render_maybe_wrap(g, executable, (IrInstructionOptionalWrap *)instruction);
+            return ir_render_optional_wrap(g, executable, (IrInstructionOptionalWrap *)instruction);
         case IrInstructionIdErrWrapCode:
             return ir_render_err_wrap_code(g, executable, (IrInstructionErrWrapCode *)instruction);
         case IrInstructionIdErrWrapPayload:

src/ir.cpp

@@ -1826,7 +1826,7 @@ static IrInstruction *ir_build_optional_wrap(IrAnalyze *ira, IrInstruction *sour
     instruction->result_loc = result_loc;
 
     ir_ref_instruction(operand, ira->new_irb.current_basic_block);
-    ir_ref_instruction(result_loc, ira->new_irb.current_basic_block);
+    if (result_loc != nullptr) ir_ref_instruction(result_loc, ira->new_irb.current_basic_block);
 
     return &instruction->base;
 }
@@ -11277,10 +11277,15 @@ static IrInstruction *ir_analyze_optional_wrap(IrAnalyze *ira, IrInstruction *so
         return &const_instruction->base;
     }
 
-    if (result_loc == nullptr) result_loc = no_result_loc();
-    IrInstruction *result_loc_inst = ir_resolve_result(ira, source_instr, result_loc, wanted_type, nullptr, true);
-    if (type_is_invalid(result_loc_inst->value.type) || instr_is_unreachable(result_loc_inst)) {
-        return result_loc_inst;
+    if (result_loc == nullptr && handle_is_ptr(wanted_type)) {
+        result_loc = no_result_loc();
+    }
+    IrInstruction *result_loc_inst = nullptr;
+    if (result_loc != nullptr) {
+        result_loc_inst = ir_resolve_result(ira, source_instr, result_loc, wanted_type, nullptr, true);
+        if (type_is_invalid(result_loc_inst->value.type) || instr_is_unreachable(result_loc_inst)) {
+            return result_loc_inst;
+        }
     }
     IrInstruction *result = ir_build_optional_wrap(ira, source_instr, wanted_type, value, result_loc_inst);
     result->value.data.rh_maybe = RuntimeHintOptionalNonNull;

test/stage1/behavior.zig

@@ -66,10 +66,10 @@ comptime {
     _ = @import("behavior/namespace_depends_on_compile_var.zig");
     _ = @import("behavior/new_stack_call.zig");
     _ = @import("behavior/null.zig");
-    _ = @import("behavior/optional.zig"); // TODO
+    _ = @import("behavior/optional.zig");
     _ = @import("behavior/pointers.zig");
     _ = @import("behavior/popcount.zig");
-    _ = @import("behavior/ptrcast.zig"); // TODO
+    _ = @import("behavior/ptrcast.zig");
     _ = @import("behavior/pub_enum.zig");
     _ = @import("behavior/ref_var_in_if_after_if_2nd_switch_prong.zig");
     _ = @import("behavior/reflection.zig");

test/stage1/behavior/optional.zig

@@ -2,11 +2,11 @@ const expect = @import("std").testing.expect;
 
 pub const EmptyStruct = struct {};
 
-//test "optional pointer to size zero struct" {
-//    var e = EmptyStruct{};
-//    var o: ?*EmptyStruct = &e;
-//    expect(o != null);
-//}
+test "optional pointer to size zero struct" {
+    var e = EmptyStruct{};
+    var o: ?*EmptyStruct = &e;
+    expect(o != null);
+}
 
 test "equality compare nullable pointers" {
     testNullPtrsEql();

test/stage1/behavior/ptrcast.zig

@@ -59,10 +59,10 @@ test "comptime ptrcast keeps larger alignment" {
     }
 }
 
-//test "implicit optional pointer to optional c_void pointer" {
-//    var buf: [4]u8 = "aoeu";
-//    var x: ?[*]u8 = &buf;
-//    var y: ?*c_void = x;
-//    var z = @ptrCast(*[4]u8, y);
-//    expect(std.mem.eql(u8, z, "aoeu"));
-//}
+test "implicit optional pointer to optional c_void pointer" {
+    var buf: [4]u8 = "aoeu";
+    var x: ?[*]u8 = &buf;
+    var y: ?*c_void = x;
+    var z = @ptrCast(*[4]u8, y);
+    expect(std.mem.eql(u8, z, "aoeu"));
+}