[clang] [llvm] [clang][SYCL] Enable -fno-gpu-rdc for SYCL (PR #218089)

[Tom Honermann via llvm-commits]

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@@ -162,6 +162,18 @@ void SPIRV::Linker::ConstructJob(Compilation &C, const JobAction &JA,
   std::string Linker = ToolChain.GetProgramPath(getShortName());
   ArgStringList CmdArgs;
 
+  // A SYCL fat binary is produced by clang-linker-wrapper, which drives the
+  // device link itself by re-invoking the driver with --sycl-link once per
+  // device image. It discards this command apart from its executable, which is
+  // eventually also ignored.
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tahonermann wrote:

Thanks, yes, that is much clearer. I agree with @bader's comment elsewhere that we should have a better way of doing this, but since this is following existing precedent, it would be better addressed in a separate PR.

https://github.com/llvm/llvm-project/pull/218089