[clang] [CUDA][HIP] Fix missing caller notes and add HD-promoted function note for deferred diagnostics (PR #187153)

[Tom Honermann via cfe-commits]

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@@ -0,0 +1,26 @@
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -fcuda-is-device -fsyntax-only \
+// RUN:   -verify %s
+// RUN: %clang_cc1 -triple nvptx64-nvidia-cuda -fcuda-is-device -fsyntax-only \
+// RUN:   -verify %s
+
+// NOTE: Do not autogenerate. Tests that "called by" notes are attached to
+// all deferred diagnostics, not just the last one in a function.
+// See https://github.com/llvm/llvm-project/issues/180638.
+
+#include "Inputs/cuda.h"
+
+__host__ void hf(); // expected-note 2{{'hf' declared here}}
+
+__device__ auto l =
+  [] { // expected-note 2{{in HD-promoted function 'operator()'}}
+    hf(); // expected-error {{reference to __host__ function 'hf' in __host__ __device__ function}}
+    hf(); // expected-error {{reference to __host__ function 'hf' in __host__ __device__ function}}
+  };
+
+__device__ void df1() {
+  l(); // expected-note 2{{called by 'df1'}}
+}
+
+__device__ void df2() {
+  l(); // expected-note 2{{called by 'df2'}}
+}
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tahonermann wrote:

While playing with this example, I discovered that we seem to be missing a diagnostic for a call to a device-only function from a `__host__ __device__` function that is called in a host-only context. I'll file a separate GH issue for this. https://godbolt.org/z/jhEhPW93G.

https://github.com/llvm/llvm-project/pull/187153