Fix hiprtc -fgpu-rdc with llvm-23

LLVM 23 does not assign GUIDs to functions linked with -mlink-builtin-bitcode-postopt,
so LTO summary emission aborts with "expected function definition ... to have an
associated value info". Link device libraries pre-opt for HIP, like the clang driver does.

Bug: https://github.com/llvm/llvm-project/pull/211155
--- a/src/comgr-compiler.cpp
+++ b/src/comgr-compiler.cpp
@@ -38,6 +38,7 @@
 #include "clang/Frontend/TextDiagnosticPrinter.h"
 #include "clang/FrontendTool/Utils.h"
 #include "clang/Options/Options.h"
+#include "llvm/Config/llvm-config.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringExtras.h"
@@ -1712,8 +1713,15 @@ amd_comgr_status_t AMDGPUCompiler::compileToBitcode(bool WithDeviceLibs) {
     // necessary for HIP (for example if HIP adopts the same AMDGPUSimplifyLibs
     // strategy that potentially introduces undefined device-library symbols),
     // we will need also apply this option in compileToRelocatable().
-    Args.push_back("-Xclang");
-    Args.push_back("-mlink-builtin-bitcode-postopt");
+#if LLVM_VERSION_MAJOR < 24
+    // LLVM 23 does not assign GUIDs to post-opt linked functions, which
+    // breaks LTO summary emission for -fgpu-rdc; HIP does not need postopt
+    if (getLanguage() != AMD_COMGR_LANGUAGE_HIP)
+#endif
+    {
+      Args.push_back("-Xclang");
+      Args.push_back("-mlink-builtin-bitcode-postopt");
+    }
   }
 
   return processFiles(AMD_COMGR_DATA_KIND_BC, ".bc");