// RUN: %clangxx -O0 -g %s -lutil -o %t && %run %t // This test depends on the glibc layout of struct sem_t and checks that we // don't leave sem_t::private uninitialized. // UNSUPPORTED: android, lsan-x86, ubsan, target-is-mips64, target-is-mips64el #include #include #include #include #include // On powerpc64be semval_t must be 64 bits even with "old" versions of glibc. #if __PPC64__ && __BIG_ENDIAN__ typedef uint64_t semval_t; // This condition needs to correspond to __HAVE_64B_ATOMICS macro in glibc. #elif (defined(__x86_64__) || defined(__aarch64__) || defined(__powerpc64__) || \ defined(__s390x__) || defined(__sparc64__) || defined(__alpha__) || \ defined(__ia64__) || defined(__m68k__)) && __GLIBC_PREREQ(2, 21) typedef uint64_t semval_t; #else typedef unsigned semval_t; #endif // glibc 2.21 has introduced some changes in the way the semaphore value is // handled for 32-bit platforms, but since these changes are not ABI-breaking // they are not versioned. On newer platforms such as ARM, there is only one // version of the symbol, so it's enough to check the glibc version. However, // for old platforms such as i386, glibc contains two or even three versions of // the sem_init symbol, and the sanitizers always pick the oldest one. // Therefore, it is not enough to rely on the __GLIBC_PREREQ macro - we should // instead check the platform as well to make sure we only expect the new // behavior on platforms where the older symbols do not exist. #if defined(__arm__) && __GLIBC_PREREQ(2, 21) #define GET_SEM_VALUE(V) ((V) >> 1) #else #define GET_SEM_VALUE(V) (V) #endif void my_sem_init(bool priv, int value, semval_t *a, unsigned char *b) { sem_t sem; memset(&sem, 0xAB, sizeof(sem)); sem_init(&sem, priv, value); char *p = (char *)&sem; memcpy(a, p, sizeof(semval_t)); memcpy(b, p + sizeof(semval_t), sizeof(char)); sem_destroy(&sem); } int main() { semval_t a; unsigned char b; my_sem_init(false, 42, &a, &b); assert(GET_SEM_VALUE(a) == 42); assert(b != 0xAB); my_sem_init(true, 43, &a, &b); assert(GET_SEM_VALUE(a) == 43); assert(b != 0xAB); }