[PATCH] Slightly nicer largefile, year2038 tests

[Paul Eggert]

* modules/largefile-tests, modules/year2038-tests (Depends-on):
Add assert-h, intprops.
* tests/test-largefile.c, tests/test-year2038.c:
Prefer compile-time to run-time tests.
Don’t assume CHAR_BIT == 8.
---
 ChangeLog               |  9 +++++++++
 modules/largefile-tests |  2 ++
 modules/year2038-tests  |  2 ++
 tests/test-largefile.c  | 27 +++++++++++----------------
 tests/test-year2038.c   |  9 ++++-----
 5 files changed, 28 insertions(+), 21 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index bd17733008..3e2682aac6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2023-04-17  Paul Eggert  <eggert@cs.ucla.edu>
+
+       Slightly nicer largefile, year2038 tests
+       * modules/largefile-tests, modules/year2038-tests (Depends-on):
+       Add assert-h, intprops.
+       * tests/test-largefile.c, tests/test-year2038.c:
+       Prefer compile-time to run-time tests.
+       Don’t assume CHAR_BIT == 8.
+
 2023-04-17  Bruno Haible  <bruno@clisp.org>
 
        MODULES.html.sh: Ensure hyperlinked files are displayable.
diff --git a/modules/largefile-tests b/modules/largefile-tests
index 3241cceb5d..544070259a 100644
--- a/modules/largefile-tests
+++ b/modules/largefile-tests
@@ -2,6 +2,8 @@ Files:
 tests/test-largefile.c
 
 Depends-on:
+assert-h
+intprops
 sys_types
 sys_stat
 
diff --git a/modules/year2038-tests b/modules/year2038-tests
index ce51559a3c..63f00ee7f8 100644
--- a/modules/year2038-tests
+++ b/modules/year2038-tests
@@ -2,6 +2,8 @@ Files:
 tests/test-year2038.c
 
 Depends-on:
+assert-h
+intprops
 
 configure.ac:
 
diff --git a/tests/test-largefile.c b/tests/test-largefile.c
index 71ee7e942d..ce5d8a0e2e 100644
--- a/tests/test-largefile.c
+++ b/tests/test-largefile.c
@@ -24,24 +24,19 @@
 
 #include <sys/types.h>
 #include <sys/stat.h>
+#include "intprops.h"
+
+/* Check the range of off_t.
+   With MSVC, this test succeeds only thanks to the 'sys_types' module.  */
+static_assert (TYPE_MAXIMUM (off_t) >> 31 >> 31 != 0);
+
+/* Check the size of the 'struct stat' field 'st_size'.
+   ,With MSVC, this test succeeds only thanks to the 'sys_stat' module.  */
+static struct stat st;
+static_assert (sizeof st.st_size == sizeof (off_t));
 
 int
 main (void)
 {
-  int result = 0;
-
-  /* Check the size of off_t.
-     With MSVC, this test succeeds only thanks to the 'sys_types' module.  */
-  if (sizeof (off_t) <= 4)
-    result |= 1;
-
-  /* Check the size of the 'struct stat' field 'st_size'.
-     With MSVC, this test succeeds only thanks to the 'sys_stat' module.  */
-  {
-    struct stat st;
-    if (sizeof (st.st_size) <= 4)
-      result |= 2;
-  }
-
-  return result;
+  return 0;
 }
diff --git a/tests/test-year2038.c b/tests/test-year2038.c
index 58c1058b13..0facf930ed 100644
--- a/tests/test-year2038.c
+++ b/tests/test-year2038.c
@@ -26,14 +26,13 @@
 #include <config.h>
 
 #include <sys/types.h>
+#include "intprops.h"
+
+/* Check the range of time_t.  */
+static_assert (TYPE_MAXIMUM (time_t) >> 31 != 0);
 
 int
 main (void)
 {
-  /* Check the size and sign of time_t.  */
-  if (sizeof (time_t) <= 4 && (time_t)-1 < 0)
-    /* time_t is only 32 bits wide and signed.  */
-    return 1;
-
   return 0;
 }
-- 
2.39.2