Commit 5fd3af9dc6ef08f23e6b64dfa6d6776371f9344a | zig

author	Andrew Kelley <andrew@ziglang.org> 2018-09-18 14:34:30-04:00
committer	Andrew Kelley <andrew@ziglang.org> 2018-09-18 14:34:30-04:00
log	5fd3af9dc6ef08f23e6b64dfa6d6776371f9344a
tree	ae86c5cefa78386e0470deb89856f61f4c78bf2b
parent	1fc2019031ef427e02acc88d7ce1c15372556c4d
signature	Commit is signed but in an unrecognized format.

fix implicit cast of packed struct field to const ptr

closes #966

2 files changed, 34 insertions(+), 14 deletions(-)

src
- ir.cpp
test
- cases
  - struct.zig

src/ir.cpp+18-14

 @@ -10015,21 +10015,25 @@ static IrInstruction *ir_analyze_cast_ref(IrAnalyze *ira, IrInstruction *source_
     if (value->id == IrInstructionIdLoadPtr) {
         IrInstructionLoadPtr *load_ptr_inst = (IrInstructionLoadPtr *)value;
-        return load_ptr_inst->ptr;
+        ConstCastOnly const_cast_result = types_match_const_cast_only(ira, wanted_type,
-    } else {
+                load_ptr_inst->ptr->value.type, source_instr->source_node, false);
-        IrInstruction *new_instruction = ir_build_ref(&ira->new_irb, source_instr->scope,
+        if (const_cast_result.id == ConstCastResultIdInvalid)
-                source_instr->source_node, value, true, false);
+            return ira->codegen->invalid_instruction;
-        new_instruction->value.type = wanted_type;
+        if (const_cast_result.id == ConstCastResultIdOk)
+            return load_ptr_inst->ptr;
+    }
+    IrInstruction *new_instruction = ir_build_ref(&ira->new_irb, source_instr->scope,
+            source_instr->source_node, value, true, false);
+    new_instruction->value.type = wanted_type;
-        ZigType *child_type = wanted_type->data.pointer.child_type;
+    ZigType *child_type = wanted_type->data.pointer.child_type;
-        if (type_has_bits(child_type)) {
+    if (type_has_bits(child_type)) {
-            ZigFn *fn_entry = exec_fn_entry(ira->new_irb.exec);
+        ZigFn *fn_entry = exec_fn_entry(ira->new_irb.exec);
-            assert(fn_entry);
+        assert(fn_entry);
-            fn_entry->alloca_list.append(new_instruction);
+        fn_entry->alloca_list.append(new_instruction);
-        }
-        ir_add_alloca(ira, new_instruction, child_type);
-        return new_instruction;
     }
+    ir_add_alloca(ira, new_instruction, child_type);
+    return new_instruction;
 }
 static IrInstruction *ir_analyze_null_to_maybe(IrAnalyze *ira, IrInstruction *source_instr, IrInstruction *value, ZigType *wanted_type) {
 @@ -11057,7 +11061,7 @@ static IrInstruction *ir_analyze_cast(IrAnalyze *ira, IrInstruction *source_inst
         }
     }
-    // enum to &const union which has the enum as the tag type
+    // enum to *const union which has the enum as the tag type
     if (actual_type->id == ZigTypeIdEnum && wanted_type->id == ZigTypeIdPointer) {
         ZigType *union_type = wanted_type->data.pointer.child_type;
         if (union_type->data.unionation.decl_node->data.container_decl.auto_enum ||

test/cases/struct.zig+16

...	@@ -437,3 +437,19 @@ test "call method with mutable reference to struct with no fields" {	...	@@ -437,3 +437,19 @@ test "call method with mutable reference to struct with no fields" {
437	assert(S.do(&s));	437	assert(S.do(&s));
438	assert(s.do());	438	assert(s.do());
439	}	439	}
		440
		441	test "implicit cast packed struct field to const ptr" {
		442	const LevelUpMove = packed struct {
		443	move_id: u9,
		444	level: u7,
		445
		446	fn toInt(value: *const u7) u7 {
		447	return value.*;
		448	}
		449	};
		450
		451	var lup: LevelUpMove = undefined;
		452	lup.level = 12;
		453	const res = LevelUpMove.toInt(lup.level);
		454	assert(res == 12);
		455	}