diff --git a/src/gtest-death-test.cc b/src/gtest-death-test.cc index 36a2e3a7..de50ba74 100644 --- a/src/gtest-death-test.cc +++ b/src/gtest-death-test.cc @@ -1062,8 +1062,19 @@ static pid_t ExecDeathTestSpawnChild(char* const* argv, int close_fd) { void* const stack = mmap(NULL, stack_size, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0); GTEST_DEATH_TEST_CHECK_(stack != MAP_FAILED); + + // Maximum stack alignment in bytes: For a downward-growing stack, this + // amount is subtracted from size of the stack space to get an address + // that is within the stack space and is aligned on all systems we care + // about. As far as I know there is no ABI with stack alignment greater + // than 64. We assume stack and stack_size already have alignment of + // kMaxStackAlignment. + const size_t kMaxStackAlignment = 64; void* const stack_top = - static_cast(stack) + (stack_grows_down ? stack_size : 0); + static_cast(stack) + + (stack_grows_down ? stack_size - kMaxStackAlignment : 0); + GTEST_DEATH_TEST_CHECK_(stack_size > kMaxStackAlignment && + reinterpret_cast(stack_top) % kMaxStackAlignment == 0); child_pid = clone(&ExecDeathTestChildMain, stack_top, SIGCHLD, &args);