tests: Make g_aligned_alloc tests fail if preconditions aren't checked

Previously, these tests would always pass. If the precondition check
failed (as we want it to), the subprocess would exit unsuccessfully;
but if the precondition check wrongly passed, the subprocess would
continue, allocate a nonzero amount of memory, and fail the
g_assert_null(), resulting in the subprocess exiting unsuccessfully
and the test still passing.

Signed-off-by: Simon McVittie <smcv@collabora.com>

glib/tests/utils.c

@@ -922,7 +922,7 @@ aligned_alloc_nz (void)
 
   /* Test an alignment that’s zero */
   a = g_aligned_alloc (16, sizeof(char), 0);
-  g_assert_null (a);
+  g_aligned_free (a);
   exit (0);
 }
 
@@ -933,7 +933,7 @@ aligned_alloc_npot (void)
 
   /* Test an alignment that’s not a power of two */
   a = g_aligned_alloc (16, sizeof(char), 15);
-  g_assert_null (a);
+  g_aligned_free (a);
   exit (0);
 }
 
@@ -944,7 +944,7 @@ aligned_alloc_nmov (void)
 
   /* Test an alignment that’s not a multiple of sizeof(void*) */
   a = g_aligned_alloc (16, sizeof(char), sizeof(void *) / 2);
-  g_assert_null (a);
+  g_aligned_free (a);
   exit (0);
 }