[2/3] nptl: Change tst-typesizes to _Static_assert

Instead of rely on runtime check to assure correct pthread types
size a better strategy would use _Static_assert to trigger an error
on build time (and thus allowing to check to potentially ABI breakage
on cross-compiling make check).

Checked on x86_64-linux-gnu and with a build check for all affected
ABIs (aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabihf,
hppa-linux-gnu, i686-linux-gnu, ia64-linux-gnu, m68k-linux-gnu,
microblaze-linux-gnu, mips64-linux-gnu, mips64-n32-linux-gnu,
mips-linux-gnu, powerpc64le-linux-gnu, powerpc-linux-gnu,
s390-linux-gnu, s390x-linux-gnu, sh4-linux-gnu, sparc64-linux-gnu,
sparcv9-linux-gnu, tilegx-linux-gnu, tilegx-linux-gnu-x32,
tilepro-linux-gnu, x86_64-linux-gnu, and x86_64-linux-x32).

	* nptl/tst-typesizes.c: Make sizes check _Static_asserts at
	built time.
---
 ChangeLog            |  3 ++
 nptl/tst-typesizes.c | 77 +++++++++++++---------------------------------------
 2 files changed, 22 insertions(+), 58 deletions(-)

Ping.


On 19/10/2017 19:00, Adhemerval Zanella wrote:
> Instead of rely on runtime check to assure correct pthread types
> size a better strategy would use _Static_assert to trigger an error
> on build time (and thus allowing to check to potentially ABI breakage
> on cross-compiling make check).
>
> Checked on x86_64-linux-gnu and with a build check for all affected
> ABIs (aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabihf,
> hppa-linux-gnu, i686-linux-gnu, ia64-linux-gnu, m68k-linux-gnu,
> microblaze-linux-gnu, mips64-linux-gnu, mips64-n32-linux-gnu,
> mips-linux-gnu, powerpc64le-linux-gnu, powerpc-linux-gnu,
> s390-linux-gnu, s390x-linux-gnu, sh4-linux-gnu, sparc64-linux-gnu,
> sparcv9-linux-gnu, tilegx-linux-gnu, tilegx-linux-gnu-x32,
> tilepro-linux-gnu, x86_64-linux-gnu, and x86_64-linux-x32).
>
> 	* nptl/tst-typesizes.c: Make sizes check _Static_asserts at
> 	built time.
> ---
>  ChangeLog            |  3 ++
>  nptl/tst-typesizes.c | 77 +++++++++++++---------------------------------------
>  2 files changed, 22 insertions(+), 58 deletions(-)
>
> diff --git a/nptl/tst-typesizes.c b/nptl/tst-typesizes.c
> index 78ed773..3355614 100644
> --- a/nptl/tst-typesizes.c
> +++ b/nptl/tst-typesizes.c
> @@ -20,56 +20,26 @@
>  #include <pthreadP.h>
>  #include <semaphore.h>
>  
> -static const struct
> -{
> -  const char *name;
> -  size_t expected;
> -  size_t is;
> -} types[] =
> -  {
> -#define T(t, c) \
> -    { #t, c, sizeof (t) }
> -    T (pthread_attr_t, __SIZEOF_PTHREAD_ATTR_T),
> -    T (pthread_mutex_t, __SIZEOF_PTHREAD_MUTEX_T),
> -    T (pthread_mutexattr_t, __SIZEOF_PTHREAD_MUTEXATTR_T),
> -    T (pthread_cond_t, __SIZEOF_PTHREAD_COND_T),
> -    T (pthread_condattr_t, __SIZEOF_PTHREAD_CONDATTR_T),
> -    T (pthread_rwlock_t, __SIZEOF_PTHREAD_RWLOCK_T),
> -    T (pthread_rwlockattr_t, __SIZEOF_PTHREAD_RWLOCKATTR_T),
> -    T (pthread_barrier_t, __SIZEOF_PTHREAD_BARRIER_T),
> -    T (pthread_barrierattr_t, __SIZEOF_PTHREAD_BARRIERATTR_T)
> -  };
> -
>  static int
>  do_test (void)
>  {
> -  int result = 0;
> -
> -#define TEST_TYPE(name) \
> -  printf ("%s: ", #name);						      \
> -  if (sizeof (name) != sizeof (((name *) 0)->__size))			      \
> -    {									      \
> -      printf ("expected %zu, is %zu\n",					      \
> -	      sizeof (((name *) 0)->__size), sizeof (name));		      \
> -      result = 1;							      \
> -    }									      \
> -  else									      \
> -    puts ("OK")
> -
> -  TEST_TYPE (pthread_mutex_t);
> -  TEST_TYPE (pthread_cond_t);
> -  TEST_TYPE (pthread_rwlock_t);
> -
> -#define TEST_TYPE2(name, internal)					      \
> -  printf ("%s: ", #name);						      \
> -  if (sizeof (((name *) 0)->__size) < sizeof (internal))		      \
> -    {									      \
> -      printf ("expected %zu, is %zu\n",					      \
> -	      sizeof (((name *) 0)->__size), sizeof (internal));	      \
> -      result = 1;							      \
> -    }									      \
> -  else									      \
> -    puts ("OK")
> +#define TEST_TYPE(__type, __size) \
> +  _Static_assert (sizeof (__type) == __size, \
> +		  "sizeof (" #__type ") != " #__size)
> +
> +  TEST_TYPE (pthread_attr_t, __SIZEOF_PTHREAD_ATTR_T);
> +  TEST_TYPE (pthread_mutex_t, __SIZEOF_PTHREAD_MUTEX_T);
> +  TEST_TYPE (pthread_mutexattr_t, __SIZEOF_PTHREAD_MUTEXATTR_T);
> +  TEST_TYPE (pthread_cond_t, __SIZEOF_PTHREAD_COND_T);
> +  TEST_TYPE (pthread_condattr_t, __SIZEOF_PTHREAD_CONDATTR_T);
> +  TEST_TYPE (pthread_rwlock_t, __SIZEOF_PTHREAD_RWLOCK_T);
> +  TEST_TYPE (pthread_rwlockattr_t, __SIZEOF_PTHREAD_RWLOCKATTR_T);
> +  TEST_TYPE (pthread_barrier_t, __SIZEOF_PTHREAD_BARRIER_T);
> +  TEST_TYPE (pthread_barrierattr_t, __SIZEOF_PTHREAD_BARRIERATTR_T);
> +
> +#define TEST_TYPE2(__type, __internal) \
> +  _Static_assert (sizeof ((__type *) 0)->__size >= sizeof (__internal), \
> +		  "sizeof (" #__type ".__size) > sizeof (" #__internal ")")
>  
>    TEST_TYPE2 (pthread_attr_t, struct pthread_attr);
>    TEST_TYPE2 (pthread_mutexattr_t, struct pthread_mutexattr);
> @@ -80,16 +50,7 @@ do_test (void)
>    TEST_TYPE2 (sem_t, struct new_sem);
>    TEST_TYPE2 (sem_t, struct old_sem);
>  
> -  for (size_t i = 0; i < sizeof (types) / sizeof (types[0]); ++i)
> -    if (types[i].expected != types[i].is)
> -      {
> -	printf ("%s: expected %zu, is %zu\n",
> -		types[i].name, types[i].expected, types[i].is);
> -	result = 1;
> -      }
> -
> -  return result;
> +  return 0;
>  }
>  
> -#define TEST_FUNCTION do_test ()
> -#include "../test-skeleton.c"
> +#include <support/test-driver.c>

On Okt 19 2017, Adhemerval Zanella <adhemerval.zanella@linaro.org> wrote:

> Instead of rely on runtime check to assure correct pthread types
> size a better strategy would use _Static_assert to trigger an error
> on build time (and thus allowing to check to potentially ABI breakage
> on cross-compiling make check).

How about putting the static asserts in some library source?

Andreas.