| Message ID | 20180622215710.126661-2-astrachan@google.com |
|---|---|
| State | Accepted |
| Delegated to: | Petr Vorel |
| Headers | show |
| Series | ksm05: Fix build warning/error with -Wnull-dereference | expand |
Hi Alistair, > Using the Android clang build, which uses -Werror -Wnull-dereference, > the following error is seen: > testcases/kernel/mem/ksm/ksm05.c:81:3: error: indirection of > non-volatile null pointer will be deleted, not trap > [-Werror,-Wnull-dereference] > *(char *)NULL = 0; /* SIGSEGV occurs as expected. */ > ^~~~~~~~~~~~~ > testcases/kernel/mem/ksm/ksm05.c:81:3: note: consider using > __builtin_trap() or qualifying pointer with 'volatile' > 1 error generated. > Change it to "volatile char *" which avoids this build issue, without > negatively affecting the test. > Signed-off-by: Alistair Strachan <astrachan@google.com> Pushed, thanks for your patch. Kind regards, Petr
diff --git a/testcases/kernel/mem/ksm/ksm05.c b/testcases/kernel/mem/ksm/ksm05.c index f3bfbf4fa..7c3530b28 100644 --- a/testcases/kernel/mem/ksm/ksm05.c +++ b/testcases/kernel/mem/ksm/ksm05.c @@ -78,7 +78,7 @@ static void test_ksm(void) ptr = SAFE_MEMALIGN(ps, ps); if (madvise(ptr, ps, MADV_MERGEABLE) < 0) tst_brk(TBROK | TERRNO, "madvise"); - *(char *)NULL = 0; /* SIGSEGV occurs as expected. */ + *(volatile char *)NULL = 0; /* SIGSEGV occurs as expected. */ } SAFE_WAITPID(pid, &status, WUNTRACED | WCONTINUED); if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
Using the Android clang build, which uses -Werror -Wnull-dereference, the following error is seen: testcases/kernel/mem/ksm/ksm05.c:81:3: error: indirection of non-volatile null pointer will be deleted, not trap [-Werror,-Wnull-dereference] *(char *)NULL = 0; /* SIGSEGV occurs as expected. */ ^~~~~~~~~~~~~ testcases/kernel/mem/ksm/ksm05.c:81:3: note: consider using __builtin_trap() or qualifying pointer with 'volatile' 1 error generated. Change it to "volatile char *" which avoids this build issue, without negatively affecting the test. Signed-off-by: Alistair Strachan <astrachan@google.com> --- testcases/kernel/mem/ksm/ksm05.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)