Added comment explaining the surprising EIGEN_COMP_CLANG && !EIGEN_COMP_NVCC clause.
diff --git a/Eigen/src/Core/arch/GPU/Half.h b/Eigen/src/Core/arch/GPU/Half.h
index 7329757..bd0c2a0 100644
--- a/Eigen/src/Core/arch/GPU/Half.h
+++ b/Eigen/src/Core/arch/GPU/Half.h
@@ -313,6 +313,9 @@
#endif
+// The EIGEN_COMP_CLANG && !EIGEN_COMP_NVCC clause is necessary on Mac where we
+// that suspect NVCC doing device-side preprocessing with clang, but actually
+// compiling with cicc, which is obviously not clang.
#if !defined(EIGEN_HAS_NATIVE_FP16) || (EIGEN_COMP_CLANG && !EIGEN_COMP_NVCC) // Emulate support for half floats
#if EIGEN_COMP_CLANG && defined(EIGEN_CUDACC)
diff --git a/Eigen/src/Core/arch/GPU/PacketMath.h b/Eigen/src/Core/arch/GPU/PacketMath.h
index e50d162..54e4e9f 100644
--- a/Eigen/src/Core/arch/GPU/PacketMath.h
+++ b/Eigen/src/Core/arch/GPU/PacketMath.h
@@ -102,6 +102,9 @@
return make_double2(from, from);
}
+// The EIGEN_COMP_CLANG && !EIGEN_COMP_NVCC clause is necessary on Mac where we
+// that suspect NVCC doing device-side preprocessing with clang, but actually
+// compiling with cicc, which is obviously not clang.
#if defined(EIGEN_CUDA_ARCH) || defined(EIGEN_HIP_DEVICE_COMPILE) || (defined(EIGEN_CUDACC) && EIGEN_COMP_CLANG && !EIGEN_COMP_NVCC)
namespace {
