Commit f66ac9a5e704d9900d9e21cb482d7487a02e7b34 | zig

author	Andrew Kelley <andrew@ziglang.org> 2018-01-27 18:30:36-05:00
committer	Andrew Kelley <andrew@ziglang.org> 2018-01-27 18:30:36-05:00
log	f66ac9a5e704d9900d9e21cb482d7487a02e7b34
tree	3353cea0f40328a854a06f83f1562cc34812ae8f
parent	ad3e2a5da07fbfe02e0152eb3fc408a7bcf36e3c

fix crash when align 1 field before self referential...

...align 8 field as slice return type

closes #723

2 files changed, 25 insertions(+), 5 deletions(-)

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

src/analyze.cpp+11-5

 @@ -362,8 +362,10 @@ TypeTableEntry *get_pointer_to_type_extra(CodeGen *g, TypeTableEntry *child_type
     } else {
         assert(bit_offset == 0);
         parent_pointer = &child_type->pointer_parent[(is_const ? 1 : 0)];
-        if (*parent_pointer)
+        if (*parent_pointer) {
+            assert((*parent_pointer)->data.pointer.alignment == byte_alignment);
             return *parent_pointer;
+        }
     }
     type_ensure_zero_bits_known(g, child_type);
 @@ -2356,6 +2358,7 @@ static void resolve_union_zero_bits(CodeGen *g, TypeTableEntry *union_type) {
     bool create_enum_type = decl_node->data.container_decl.auto_enum || (enum_type_node == nullptr && want_safety);
     bool *covered_enum_fields;
     ZigLLVMDIEnumerator **di_enumerators;
+    uint32_t abi_alignment_so_far;
     if (create_enum_type) {
         occupied_tag_values.init(field_count);
 @@ -2377,7 +2380,7 @@ static void resolve_union_zero_bits(CodeGen *g, TypeTableEntry *union_type) {
         } else {
             tag_int_type = get_smallest_unsigned_int_type(g, field_count - 1);
         }
-        union_type->data.unionation.abi_alignment = get_abi_alignment(g, tag_int_type);
+        abi_alignment_so_far = get_abi_alignment(g, tag_int_type);
         tag_type = new_type_table_entry(TypeTableEntryIdEnum);
         buf_resize(&tag_type->name, 0);
 @@ -2408,9 +2411,10 @@ static void resolve_union_zero_bits(CodeGen *g, TypeTableEntry *union_type) {
         }
         tag_type = enum_type;
         covered_enum_fields = allocate<bool>(enum_type->data.enumeration.src_field_count);
-        union_type->data.unionation.abi_alignment = get_abi_alignment(g, enum_type);
+        abi_alignment_so_far = get_abi_alignment(g, enum_type);
     } else {
         tag_type = nullptr;
+        abi_alignment_so_far = 0;
     }
     union_type->data.unionation.tag_type = tag_type;
 @@ -2508,12 +2512,14 @@ static void resolve_union_zero_bits(CodeGen *g, TypeTableEntry *union_type) {
         uint32_t field_align_bytes = get_abi_alignment(g, field_type);
         if (field_align_bytes > biggest_align_bytes) {
             biggest_align_bytes = field_align_bytes;
-            if (biggest_align_bytes > union_type->data.unionation.abi_alignment) {
+            if (biggest_align_bytes > abi_alignment_so_far) {
-                union_type->data.unionation.abi_alignment = biggest_align_bytes;
+                abi_alignment_so_far = biggest_align_bytes;
             }
         }
     }
+    union_type->data.unionation.abi_alignment = abi_alignment_so_far;
     if (union_type->data.unionation.is_invalid)
         return;

test/cases/struct.zig+14

...	@@ -404,3 +404,17 @@ test "native bit field understands endianness" {	...	@@ -404,3 +404,17 @@ test "native bit field understands endianness" {
404	assert(bitfields.f6 == 0x6);	404	assert(bitfields.f6 == 0x6);
405	assert(bitfields.f7 == 0x77);	405	assert(bitfields.f7 == 0x77);
406	}	406	}
		407
		408	test "align 1 field before self referential align 8 field as slice return type" {
		409	const result = alloc(Expr);
		410	assert(result.len == 0);
		411	}
		412
		413	const Expr = union(enum) {
		414	Literal: u8,
		415	Question: &Expr,
		416	};
		417
		418	fn alloc(comptime T: type) []T {
		419	return []T{};
		420	}