[clang] [CUDA][HIP] Exclude external variables from constant promotion. (PR #73549)

[Artem Belevich via cfe-commits]

================
@@ -104,3 +106,14 @@ void fun() {
   (void) b<double>;
   (void) var_host_only;
 }
+
+extern __global__ void external_func();
+extern void* const external_dep[] = {
+  (void*)(external_func)
+};
+extern void* const external_arr[] = {};
+
+void* host_fun() {
+  (void) external_dep;
+  (void) external_arr;
+}
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Artem-B wrote:

There are no CHECK lines here. 

https://github.com/llvm/llvm-project/pull/73549