[foreign-jextract] Generated getters and setters do not include offsets

[Filip Krakowski]

Hi,

omitting the "--source" flags yields class files producing the expected 
result. Does this mean source code generation takes another path than 
bytecode generation? I thought that omitting the "--source" flag would 
just compile the generated sources for convenience. I also inspected the 
bytecode using javap and saw that the PathElements are there.

Best regards,
Filip

On 31.08.20 13:25, Maurizio Cimadamore wrote:
> Hi
> this seems an issue with source code generation - can you please 
> verify that w/o the --source flag the behavior is as expected?
>
> (seems like source generation is omitting layout paths when generating 
> VH accessors)
>
> Maurizio
>
> On 31/08/2020 11:35, Filip Krakowski wrote:
>> Hi,
>>
>> I just noticed that jextract's generated getters and setters always 
>> access the provided MemorySegment at offset 0. This looks like a bug 
>> to me.
>>
>> This is the struct I used to reproduce this issue.
>>
>>    struct coordinate {
>>       int x;
>>       int y;
>>    };
>>
>>
>> And this is the code jextract generated from it (source mode).
>>
>>    private static final MemoryLayout coordinate$struct$LAYOUT_ 
>> =MemoryLayout.ofStruct(
>>         C_INT.withName("x"),
>>         C_INT.withName("y")
>>    ).withName("coordinate");
>>
>>    public static jdk.incubator.foreign.MemoryLayout
>>    coordinate$struct$LAYOUT() {return coordinate$struct$LAYOUT_; }
>>
>>    private static final MemoryLayout coordinate$x$LAYOUT_ =C_INT;
>>    public static jdk.incubator.foreign.MemoryLayout 
>> coordinate$x$LAYOUT() {return coordinate$x$LAYOUT_; }
>>
>>    private static final VarHandle coordinate$x$VH_ 
>> =coordinate$x$LAYOUT_.varHandle(int.class);
>>    public static java.lang.invoke.VarHandle coordinate$x$VH() {return 
>> coordinate$x$VH_; }
>>
>>    private static final MemoryLayout coordinate$y$LAYOUT_ =C_INT;
>>    public static jdk.incubator.foreign.MemoryLayout 
>> coordinate$y$LAYOUT() {return coordinate$y$LAYOUT_; }
>>
>>    private static final VarHandle coordinate$y$VH_ 
>> =coordinate$y$LAYOUT_.varHandle(int.class);
>>    public static java.lang.invoke.VarHandle coordinate$y$VH() {return 
>> coordinate$y$VH_; }
>>
>>
>> Here I allocate the struct, set both fields and print them afterwards.
>>
>>    try (var segment =coordinate.allocate()) {
>>         coordinate.x$set(segment,1);
>>         coordinate.y$set(segment,2);
>>
>>         System.out.println(coordinate.x$get(segment));
>>         System.out.println(coordinate.y$get(segment));
>>    }
>>
>>
>> This will print "2" twice, although "x" should be set to "1" in my 
>> understanding.
>>
>> I am using the latest build (commit 
>> 4d7888c040767760b6250130ef6024ea16b43461).
>>
>>
>> Best regards,
>> Filip