Merge drbd-9.1/8597f3d59 'compat: Workaround for Linux-6.12 bug in co…

…mpat test have_strscpy.c'

drbd/drbd-kernel-compat/tests/have_strscpy.c

@@ -2,6 +2,19 @@
 
 #include <linux/string.h>
 
+/*
+ * For making it compatible with linux-6.12:
+ * Work around <linux/compiler.h> defines __must_be_array() and __must_be_cstr() and both expand to
+ * BUILD_BUG_ON_ZERO(), but <linux/build_bug.h> defines BUILD_BUG_ON_ZERO(). <linux/compiler.h> does
+ * not include <linux/build_bug.h> and Linus does not want that.
+ *
+ * See https://lore.kernel.org/linux-kernel/[email protected]/T/#t
+ *
+ */
+#ifndef BUILD_BUG_ON_ZERO
+#define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
+#endif
+
 ssize_t foo(char *dest, const char *src, size_t count)
 {
 	return strscpy(dest, src, count);