tdb: enforce hashing, via example hash in old rwlocks entry in header.
[ccan] / ccan / build_assert / test /
drwxr-xr-x   ..
-rw-r--r-- 153 compile_fail-expr.c
-rw-r--r-- 135 compile_fail.c
-rw-r--r-- 116 compile_ok.c
-rw-r--r-- 185 run-EXPR_BUILD_ASSERT.c