[clang] Add sycl_external attribute (PR #140282)

[via cfe-commits]

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@@ -12909,6 +12909,10 @@ bool ASTContext::DeclMustBeEmitted(const Decl *D) {
   if (D->hasAttr<WeakRefAttr>())
     return false;
 
+  if (LangOpts.SYCLIsDevice &&
+       (!D->hasAttr<SYCLKernelEntryPointAttr>() || !D->hasAttr<SYCLExternalAttr>()))
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schittir wrote:

Good catch. Thank you!

https://github.com/llvm/llvm-project/pull/140282