Re: LLVM 16 (opaque pointers)

Hi,

On 2023-05-21 15:01:41 +1200, Thomas Munro wrote:
> *For anyone working with this type of IR generation code and
> questioning their sanity, I can pass on some excellent advice I got
> from Andres: build LLVM yourself with assertions enabled, as they
> catch some classes of silly mistake that otherwise just segfault
> inscrutably on execution.

Hm. I think we need a buildfarm animal with an assertion enabled llvm 16 once
we merge this. I think after an upgrade my buildfarm machine has the necessary
resources.

> @@ -150,7 +150,7 @@ llvm_compile_expr(ExprState *state)
>
> /* create function */
> eval_fn = LLVMAddFunction(mod, funcname,
> - llvm_pg_var_func_type("TypeExprStateEvalFunc"));
> + llvm_pg_var_func_type("ExecInterpExprStillValid"));

Hm, that's a bit ugly. But ...

> @@ -77,9 +80,44 @@ extern Datum AttributeTemplate(PG_FUNCTION_ARGS);
> Datum
> AttributeTemplate(PG_FUNCTION_ARGS)
> {
> + PGFunction fp PG_USED_FOR_ASSERTS_ONLY;
> +
> + fp = &AttributeTemplate;
> PG_RETURN_NULL();
> }

Other parts of the file do this by putting the functions into
referenced_functions[], i'd copy that here and below.

> +void
> +ExecEvalSubroutineTemplate(ExprState *state,
> + struct ExprEvalStep *op,
> + ExprContext *econtext)
> +{
> + ExecEvalSubroutine fp PG_USED_FOR_ASSERTS_ONLY;
> +
> + fp = &ExecEvalSubroutineTemplate;
> +}
> +
> +extern bool ExecEvalBoolSubroutineTemplate(ExprState *state,
> + struct ExprEvalStep *op,
> + ExprContext *econtext);
> +bool
> +ExecEvalBoolSubroutineTemplate(ExprState *state,
> + struct ExprEvalStep *op,
> + ExprContext *econtext)
> +{
> + ExecEvalBoolSubroutine fp PG_USED_FOR_ASSERTS_ONLY;
> +
> + fp = &ExecEvalBoolSubroutineTemplate;
> + return false;
> +}
> +

Thanks for working on this!

Greetings,

Andres Freund