[foreign-jextract] Wrong MemoryLayout and VarHandle carrier for integer field

[sundararajan.athijegannathan at oracle.com]

I don't have the complete dependencies on my machine

I locally filled the struct definition you gave with appropriate 
dependencies (dummy struct, enum declarations) and jextracted it.

I see C_INT is being generated as layout for sq_sig_all. I suspect most 
likely you're using old panama build. I'd recommend building latest 
panama build from repo and trying your header with the same.

-Sundar

On 27/08/20 4:14 pm, Filip Krakowski wrote:
> Hi,
>
> I would like to report a bug regarding jextract. The header file 
> (https://github.com/linux-rdma/rdma-core/blob/master/libibverbs/verbs.h) 
> I give to jextract contains the following struct.
>
>    struct ibv_qp_init_attr {
>             void                   *qp_context;
>             struct ibv_cq          *send_cq;
>             struct ibv_cq          *recv_cq;
>             struct ibv_srq         *srq;
>             struct ibv_qp_cap       cap;
>             enum ibv_qp_type        qp_type;
>             int                     sq_sig_all;
>    };
>
>
> The Code generated for the "sq_sig_all" field looks like this.
>
>    private static final MemoryLayout sq_sig_all$LAYOUT_ =C_BOOL;
>    private static final VarHandle sq_sig_all$VH_ 
> =sq_sig_all$LAYOUT_.varHandle(byte.class);
>
>    public static int sq_sig_all$get(MemorySegment seg) {
>         return (int)verbs_h$constants$3.sq_sig_all$VH().get(seg);
>    }
>
>    public static void 
> sq_sig_all$set(jdk.incubator.foreign.MemorySegment seg,int x) {
>         verbs_h$constants$3.sq_sig_all$VH().set(seg, x);
>    }
>
> As you can see jextract chooses "C_BOOL" as the MemoryLayout for the 
> "sq_sig_all" field and uses "byte" for the VarHandle's carrier. In 
> contrast to this, getters and setters work with "int" which leads to 
> an Exception during runtime.
>
>    java.lang.invoke.WrongMethodTypeException: cannot convert
>    MethodHandle(VarHandle,MemorySegment,byte)void to
>    (VarHandle,MemorySegment,int)void
>
>