llvm-project/clang/test/CodeGenObjC/ubsan-array-bounds.m
serge-sans-paille f764dc99b3 [clang] Introduce -fstrict-flex-arrays=<n> for stricter handling of flexible arrays
Some code [0] consider that trailing arrays are flexible, whatever their size.
Support for these legacy code has been introduced in
f8f632498307d22e10fab0704548b270b15f1e1e but it prevents evaluation of
__builtin_object_size and __builtin_dynamic_object_size in some legit cases.

Introduce -fstrict-flex-arrays=<n> to have stricter conformance when it is
desirable.

n = 0: current behavior, any trailing array member is a flexible array. The default.
n = 1: any trailing array member of undefined, 0 or 1 size is a flexible array member
n = 2: any trailing array member of undefined or 0 size is a flexible array member

This takes into account two specificities of clang: array bounds as macro id
disqualify FAM, as well as non standard layout.

Similar patch for gcc discuss here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836

[0] https://docs.freebsd.org/en/books/developers-handbook/sockets/#sockets-essential-functions
2022-07-18 12:45:52 +02:00

17 lines
398 B
Objective-C

// RUN: %clang_cc1 -x objective-c -emit-llvm -triple x86_64-apple-macosx10.10.0 -Wno-objc-root-class -fsanitize=array-bounds %s -o - | FileCheck %s
@interface FlexibleArray1 {
@public
char chars[0];
}
@end
@implementation FlexibleArray1
@end
// CHECK-LABEL: test_FlexibleArray1
char test_FlexibleArray1(FlexibleArray1 *FA1) {
// CHECK-NOT: !nosanitize
return FA1->chars[1];
// CHECK: }
}