[PATCH] D27334: [OpenCL] Ambiguous function call.

[Alexey Bader via Phabricator via cfe-commits]

bader added a comment.

In https://reviews.llvm.org/D27334#611703, @Anastasia wrote:

> This change seems to modify normal C behavior again. Is there any strong motivation for doing this and if yes could it be done generically with C?


Motivation:

  // Non-portable OpenCL 1.2 code 
  __kernel void foo(global float* out) {
    out[get_global_id(0)] = sin(get_global_id(0));
  }

This program compiles fine on OpenCL platform w/o doubles support and fails otherwise.
If OpenCL driver supports doubles it provides at least two versions of 'sin' built-in math function and compiler will not be able to choose the right one for 'size_t' argument.
The goal of this warning is to let OpenCL developer know about potential issues with code portability.

This might be not so serious issue for C, since C doesn't support function overloading, whereas OpenCL built-in functions library must overload most of the functions.


https://reviews.llvm.org/D27334