[clang] [llvm] Enable OpenCL hostcall printf (WIP) (PR #72556)

[Sameer Sahasrabuddhe via cfe-commits]

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@@ -4742,6 +4742,16 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     Args.ClaimAllArgs(options::OPT_gen_cdb_fragment_path);
   }
 
+  if (TC.getTriple().isAMDGPU() && types::isOpenCL(Input.getType())) {
+    if (Args.getLastArg(options::OPT_mprintf_kind_EQ)) {
+      CmdArgs.push_back(Args.MakeArgString(
+          "-mprintf-kind=" +
+          Args.getLastArgValue(options::OPT_mprintf_kind_EQ)));
+      // Force compiler error on invalid conversion specifiers
+      CmdArgs.push_back(Args.MakeArgString("-Werror=format-invalid-specifier"));
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ssahasra wrote:

Why is this necessary here?

https://github.com/llvm/llvm-project/pull/72556