On 2025-06-07 I added this:
> diff --git a/tests/test-stdcountof-h.c b/tests/test-stdcountof-h.c
> index cd7e03f331..5d0a9a6611 100644
> --- a/tests/test-stdcountof-h.c
> +++ b/tests/test-stdcountof-h.c
> @@ -58,6 +58,11 @@ test_func (int parameter[3])
> ASSERT (countof (unbounded) >= 0);
> #endif
>
> + {
> + extern int a, b, c;
> + ASSERT (countof (((int[]) { a, b, c })) == 3);
> + }
> +
> /* Check that countof(...) is an expression of type size_t. */
> #if !defined __cplusplus && HAVE__GENERIC
> ASSERT (_Generic (countof (bounded), size_t: 1, default: 0));
>
But this leads to a link error on MSVC 14. This patch fixes it.
2025-10-12 Bruno Haible <[email protected]>
stdcountof-h tests: Fix link error on MSVC 14 (regression 2025-06-07).
* tests/test-stdcountof-h.c (a, b, c): Define as variables on MSVC.
diff --git a/tests/test-stdcountof-h.c b/tests/test-stdcountof-h.c
index 77cfbc4dec..615cccda16 100644
--- a/tests/test-stdcountof-h.c
+++ b/tests/test-stdcountof-h.c
@@ -105,3 +105,12 @@ main ()
return test_exit_status;
}
+
+/* A definition of the variables a, b, c is not required by ISO C, because
+ these identifiers are only used as part of 'sizeof' expressions whose
+ results are integer expressions. See ISO C 23 ยง 6.9.1.(5). However,
+ MSVC 14 generates actual references to these variables. We thus need
+ to define these variables; otherwise we get link errors. */
+#if defined _MSC_VER && !defined __clang__
+int a, b, c;
+#endif
