analyze: error for infinite size struct

This commit is contained in:
Andrew Kelley 2015-12-22 13:41:33 -07:00
parent 431170d981
commit fe3ad27d5f
3 changed files with 25 additions and 1 deletions

View File

@ -273,12 +273,19 @@ static void preview_function_labels(CodeGen *g, AstNode *node, FnTableEntry *fn_
static void resolve_struct_type(CodeGen *g, ImportTableEntry *import, TypeTableEntry *struct_type) { static void resolve_struct_type(CodeGen *g, ImportTableEntry *import, TypeTableEntry *struct_type) {
assert(struct_type->id == TypeTableEntryIdStruct); assert(struct_type->id == TypeTableEntryIdStruct);
AstNode *decl_node = struct_type->data.structure.decl_node;
if (struct_type->data.structure.embedded_in_current) {
add_node_error(g, decl_node,
buf_sprintf("struct has infinite size"));
return;
}
if (struct_type->data.structure.fields) { if (struct_type->data.structure.fields) {
// we already resolved this type. skip // we already resolved this type. skip
return; return;
} }
AstNode *decl_node = struct_type->data.structure.decl_node;
assert(struct_type->di_type); assert(struct_type->di_type);
@ -293,6 +300,9 @@ static void resolve_struct_type(CodeGen *g, ImportTableEntry *import, TypeTableE
uint64_t first_field_align_in_bits = 0; uint64_t first_field_align_in_bits = 0;
uint64_t offset_in_bits = 0; uint64_t offset_in_bits = 0;
// this field should be set to true only during the recursive calls to resolve_struct_type
struct_type->data.structure.embedded_in_current = true;
for (int i = 0; i < field_count; i += 1) { for (int i = 0; i < field_count; i += 1) {
AstNode *field_node = decl_node->data.struct_decl.fields.at(i); AstNode *field_node = decl_node->data.struct_decl.fields.at(i);
TypeStructField *type_struct_field = &struct_type->data.structure.fields[i]; TypeStructField *type_struct_field = &struct_type->data.structure.fields[i];
@ -321,6 +331,7 @@ static void resolve_struct_type(CodeGen *g, ImportTableEntry *import, TypeTableE
offset_in_bits += type_struct_field->type_entry->size_in_bits; offset_in_bits += type_struct_field->type_entry->size_in_bits;
} }
struct_type->data.structure.embedded_in_current = false;
LLVMStructSetBody(struct_type->type_ref, element_types, field_count, false); LLVMStructSetBody(struct_type->type_ref, element_types, field_count, false);

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@ -43,6 +43,9 @@ struct TypeTableEntryStruct {
bool is_packed; bool is_packed;
int field_count; int field_count;
TypeStructField *fields; TypeStructField *fields;
// set this flag temporarily to detect infinite loops
bool embedded_in_current;
}; };
struct TypeTableEntryNumLit { struct TypeTableEntryNumLit {

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@ -828,6 +828,16 @@ fn f() {
} }
)SOURCE", 2, ".tmp_source.zig:3:21: error: expected type 'i32', got 'void'", )SOURCE", 2, ".tmp_source.zig:3:21: error: expected type 'i32', got 'void'",
".tmp_source.zig:4:15: error: incompatible types: 'i32' and 'void'"); ".tmp_source.zig:4:15: error: incompatible types: 'i32' and 'void'");
add_compile_fail_case("direct struct loop", R"SOURCE(
struct A { a : A, }
)SOURCE", 1, ".tmp_source.zig:2:1: error: struct has infinite size");
add_compile_fail_case("indirect struct loop", R"SOURCE(
struct A { b : B, }
struct B { c : C, }
struct C { a : A, }
)SOURCE", 1, ".tmp_source.zig:2:1: error: struct has infinite size");
} }
static void print_compiler_invocation(TestCase *test_case) { static void print_compiler_invocation(TestCase *test_case) {