In-process compilation breaks compile_source_to_executable test, as it attempts to
build .so as fatbin, and some options does not work with unpatched LLVM.
--- a/src/comgr-compiler.cpp
+++ b/src/comgr-compiler.cpp
@@ -1226,10 +1226,7 @@ amd_comgr_status_t AMDGPUCompiler::compileToFatBin() {
     return AMD_COMGR_STATUS_ERROR_INVALID_ARGUMENT;
   }
 
-  // This is a workaround to support HIP OOP Fatbin Compilation
-  CompileOOP = true;
   auto Status = processFiles(AMD_COMGR_DATA_KIND_FATBIN, ".fatbin");
-  CompileOOP = false;
 
   return Status;
 }
--- a/src/comgr-compiler.h
+++ b/src/comgr-compiler.h
@@ -102,7 +102,7 @@ class AMDGPUCompiler {
   std::string ClangIncludePath;
   std::string ClangIncludePath2;
   /// Perform out-of-process compilation.
-  bool CompileOOP = false;
+  bool CompileOOP = true;
   /// Precompiled header file paths.
   llvm::SmallVector<llvm::SmallString<128>, 2> PrecompiledHeaders;
   /// Arguments common to all driver invocations in the current action.