authorgravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2020-03-19 17:23:53-04:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2020-03-19 17:23:53-04:00
log160367e0ddcb36b6957e603d869507b9d7542edc
tree300e305100b96c1ad1b842f0efb43892d47b9b62
parent6b6f2fcf96b0d8493be45b484226ea8ae9a83a88
signaturelock-open Commit is signed but in an unrecognized format.

fix compile error for reading past end of pointer casted array

2 files changed, 37 insertions(+), 12 deletions(-)

src/ir.cpp+27-1
......@@ -19971,6 +19971,7 @@ static Error ir_read_const_ptr(IrAnalyze *ira, CodeGen *codegen, AstNode *source
1997119971 buf_write_value_bytes(codegen, (uint8_t*)buf_ptr(&buf), pointee);
1997219972 if ((err = buf_read_value_bytes(ira, codegen, source_node, (uint8_t*)buf_ptr(&buf), out_val)))
1997319973 return err;
19974 buf_deinit(&buf);
1997419975 return ErrorNone;
1997519976 }
1997619977
......@@ -19990,7 +19991,31 @@ static Error ir_read_const_ptr(IrAnalyze *ira, CodeGen *codegen, AstNode *source
1999019991 dst_size, buf_ptr(&pointee->type->name), src_size));
1999119992 return ErrorSemanticAnalyzeFail;
1999219993 }
19993 case ConstPtrSpecialSubArray:
19994 case ConstPtrSpecialSubArray: {
19995 ZigValue *array_val = ptr_val->data.x_ptr.data.base_array.array_val;
19996 assert(array_val->type->id == ZigTypeIdArray);
19997 if (array_val->data.x_array.special != ConstArraySpecialNone)
19998 zig_panic("TODO");
19999 if (dst_size > src_size) {
20000 size_t elem_index = ptr_val->data.x_ptr.data.base_array.elem_index;
20001 opt_ir_add_error_node(ira, codegen, source_node,
20002 buf_sprintf("attempt to read %" ZIG_PRI_usize " bytes from %s at index %" ZIG_PRI_usize " which is %" ZIG_PRI_usize " bytes",
20003 dst_size, buf_ptr(&array_val->type->name), elem_index, src_size));
20004 return ErrorSemanticAnalyzeFail;
20005 }
20006 size_t elem_size = src_size;
20007 size_t elem_count = (dst_size % elem_size == 0) ? (dst_size / elem_size) : (dst_size / elem_size + 1);
20008 Buf buf = BUF_INIT;
20009 buf_resize(&buf, elem_count * elem_size);
20010 for (size_t i = 0; i < elem_count; i += 1) {
20011 ZigValue *elem_val = &array_val->data.x_array.data.s_none.elements[i];
20012 buf_write_value_bytes(codegen, (uint8_t*)buf_ptr(&buf) + (i * elem_size), elem_val);
20013 }
20014 if ((err = buf_read_value_bytes(ira, codegen, source_node, (uint8_t*)buf_ptr(&buf), out_val)))
20015 return err;
20016 buf_deinit(&buf);
20017 return ErrorNone;
20018 }
1999420019 case ConstPtrSpecialBaseArray: {
1999520020 ZigValue *array_val = ptr_val->data.x_ptr.data.base_array.array_val;
1999620021 assert(array_val->type->id == ZigTypeIdArray);
......@@ -20014,6 +20039,7 @@ static Error ir_read_const_ptr(IrAnalyze *ira, CodeGen *codegen, AstNode *source
2001420039 }
2001520040 if ((err = buf_read_value_bytes(ira, codegen, source_node, (uint8_t*)buf_ptr(&buf), out_val)))
2001620041 return err;
20042 buf_deinit(&buf);
2001720043 return ErrorNone;
2001820044 }
2001920045 case ConstPtrSpecialBaseStruct:
test/compile_errors.zig+10-11
......@@ -1903,17 +1903,16 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
19031903 "tmp.zig:7:15: error: switch must handle all possibilities",
19041904 });
19051905
1906 // TODO uncomment before merging branch
1907 //cases.add("reading past end of pointer casted array",
1908 // \\comptime {
1909 // \\ const array: [4]u8 = "aoeu".*;
1910 // \\ const sub_array = array[1..];
1911 // \\ const int_ptr = @ptrCast(*const u24, sub_array);
1912 // \\ const deref = int_ptr.*;
1913 // \\}
1914 //, &[_][]const u8{
1915 // "tmp.zig:5:26: error: attempt to read 4 bytes from [4]u8 at index 1 which is 3 bytes",
1916 //});
1906 cases.add("reading past end of pointer casted array",
1907 \\comptime {
1908 \\ const array: [4]u8 = "aoeu".*;
1909 \\ const sub_array = array[1..];
1910 \\ const int_ptr = @ptrCast(*const u24, sub_array);
1911 \\ const deref = int_ptr.*;
1912 \\}
1913 , &[_][]const u8{
1914 "tmp.zig:5:26: error: attempt to read 4 bytes from [4]u8 at index 1 which is 3 bytes",
1915 });
19171916
19181917 cases.add("error note for function parameter incompatibility",
19191918 \\fn do_the_thing(func: fn (arg: i32) void) void {}