[PATCH] D10725: Improve testing for the C API

[Amaury SECHET via llvm-commits]

deadalnix added inline comments.

================
Comment at: tools/llvm-c-test/echo.cpp:82
@@ +81,3 @@
+        LLVMGetParamTypes(Src, Params);
+        for (unsigned i = 0; i < ParamCount; i++) {
+          Params[i] = clone_type(Params[i], Ctx);
----------------
dblaikie wrote:
> deadalnix wrote:
> > echristo wrote:
> > > Can you try to explain a different way? I'm not sure what you mean.
> > Sure. The trick part is that LLVMGetParamTypes require a buffer passed down as a pointer and will fill it all. So we need to create a buffer and fill it. Vector like API do not really lend itself to this.
> It's pretty common to use std::vector when interacting with C APIs from C++ - not sure if we're picturing the same thing. This is what I'd imagine:
> 
>   std::vector<LLVMTypeRef> Params(ParamCount);
>   LLVMGetParamTypes(Src, Params.data());
>   ... (probably use Params directly without using ParamCount at this point)
>   ... (skip the "if ParamCount / free" part, because it'll be cleaned up naturally)
> 
> Is there something about that that doesn't work/did you have something else in mind, etc?
Yeah I can do that, but at the end, the Vector is fed to the C API as pointer + length, so none of the feature of vector are use or are usable.


http://reviews.llvm.org/D10725