compat.opencl

// Behavioural test: compat.opencl builds a loader a consumer can link, and the
// loader can enumerate whatever the machine advertises.
//
// Zero platforms is a pass. Every CI runner in this repository has no OpenCL
// driver, and CL_PLATFORM_NOT_FOUND_KHR is the loader's own answer for that
// case; it proves the trampolines are linked and the ICD scan ran. A machine
// with a driver, or with xim:pocl announced through OCL_ICD_FILENAMES, lists
// its platforms and devices; the test prints them so the log says which case
// it measured.
//
// Classic includes rather than `import std;`: `CL/cl_platform.h` includes
// `<xmmintrin.h>`, which pulls `<stdlib.h>` into the global module before the
// std module is imported, and GCC then reports conflicting language linkage
// for the declarations both provide.
#include <cstdio>
#if !defined(HAVE_OPENCL_LOADER)
int main() {
    std::printf("compat.opencl: skipped (no windows entry; drivers are enumerated through the registry there)\n");
    return 0;
}
#else
#define CL_TARGET_OPENCL_VERSION 300
// …