// RUN: %clang_tysan -O0 %s -o %t && %run %t >%t.out 2>&1 // RUN: FileCheck %s < %t.out // https://github.com/llvm/llvm-project/issues/47137 #include #include #include void f(int m) { int n = (4 * m + 2) / 3; uint64_t *a = malloc(n * sizeof(uint64_t)); uint64_t *b = malloc(n * sizeof(uint64_t)); uint64_t aa[] = {0xffff3e0000000001, 0x22eaf0b680a88c16, 0x5a65d25ac40e20f3, 0x34e7ac346236953e, 0x9dea3e0a26c6ba89, 0x0000000000000000, 0x0000000000000000, 0x0000000000000000}; uint64_t bb[] = {0x0000000024c0ffff, 0x000000004634d940, 0x00000000219d18ef, 0x0000000000154519, 0x000000000000035f, 0x0000000000000000, 0x0000000000000000, 0x0000000000000000}; char l[20]; l[0] = 0; for (int i = 0; i < n; i++) { a[i] = aa[i] + l[0] - '0'; b[i] = bb[i] + l[0] - '0'; } // CHECK: TypeSanitizer: type-aliasing-violation on address // CHECK-NEXT: READ of size 2 at {{.+}} with type short accesses an existing object of type long // CHECK-NEXT: in f {{.*/?}}violation-pr47137.c:31 for (int i = 0, j = 0; j < 4 * m; i += 4, j += 3) { for (int k = 0; k < 3; k++) { ((uint16_t *)a)[j + k] = ((uint16_t *)a)[i + k]; ((uint16_t *)b)[j + k] = ((uint16_t *)b)[i + k]; } } printf("a: %016llx\n", a[0]); free(a); free(b); } int main() { f(6); }