structeq: fix case where we mark padding as unknown.

[ccan] / ccan / structeq / test / compile_fail-unexpected-negative-padding.c

diff --git a/ccan/structeq/test/compile_fail-unexpected-negative-padding.c b/ccan/structeq/test/compile_fail-unexpected-negative-padding.c
new file mode 100644 (file)
index 0000000..2c63b23
--- /dev/null
+++ b/ccan/structeq/test/compile_fail-unexpected-negative-padding.c
@@ -0,0 +1,20 @@
+#include <ccan/structeq/structeq.h>
+
+struct mydata {
+       int start, end;
+       int pad;
+};
+#ifdef FAIL
+#define PADDING -1
+#else
+#define PADDING -(int)sizeof(int)
+#endif
+
+STRUCTEQ_DEF(mydata, PADDING, start, end);
+
+int main(void)
+{
+       struct mydata a = { 0, 100 };
+
+       return mydata_eq(&a, &a);
+}