reallocarray-tests: port to weird platforms

* tests/test-reallocarray.c (main): Don’t assume that
PTRDIFF_MAX / 2 + 1 <= SIZE_MAX.  POSIX allows platforms
where this isn’t true, though I don’t know of any examples.

2 files changed, 11 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index 08f9c7b24c..a110970f3a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2021-05-30  Paul Eggert  <eggert@cs.ucla.edu>
 
+	reallocarray-tests: port to weird platforms
+	* tests/test-reallocarray.c (main): Don’t assume that
+	PTRDIFF_MAX / 2 + 1 <= SIZE_MAX.  POSIX allows platforms
+	where this isn’t true, though I don’t know of any examples.
+
 	dfa, etc.: prefer xreallocarray to older name
 	* lib/dfa.c (addtok_mb, realloc_trans_if_necessary, enlist):
 	* lib/readtokens.c (readtokens):
diff --git a/tests/test-reallocarray.c b/tests/test-reallocarray.c
index f0839ff748..ff90962a96 100644
--- a/tests/test-reallocarray.c
+++ b/tests/test-reallocarray.c
@@ -36,9 +36,12 @@ main ()
     {
       void *volatile p = NULL;
 
-      p = reallocarray (p, PTRDIFF_MAX / n + 1, n);
-      ASSERT (p == NULL);
-      ASSERT (errno == ENOMEM);
+      if (PTRDIFF_MAX / n + 1 <= SIZE_MAX)
+        {
+          p = reallocarray (p, PTRDIFF_MAX / n + 1, n);
+          ASSERT (p == NULL);
+          ASSERT (errno == ENOMEM);
+        }
 
       p = reallocarray (p, SIZE_MAX / n + 1, n);
       ASSERT (p == NULL);