Add back llvm::make_unique uses for older versions

Author: nikic

src/rustllvm/ArchiveWrapper.cpp

@@ -89,7 +89,11 @@ extern "C" void LLVMRustDestroyArchive(LLVMRustArchiveRef RustArchive) {
 extern "C" LLVMRustArchiveIteratorRef
 LLVMRustArchiveIteratorNew(LLVMRustArchiveRef RustArchive) {
   Archive *Archive = RustArchive->getBinary();
+#if LLVM_VERSION_GE(10, 0)
   std::unique_ptr<Error> Err = std::make_unique<Error>(Error::success());
+#else
+  std::unique_ptr<Error> Err = llvm::make_unique<Error>(Error::success());
+#endif
   auto Cur = Archive->child_begin(*Err);
   if (*Err) {
     LLVMRustSetLastError(toString(std::move(*Err)).c_str());

src/rustllvm/Linker.cpp

@@ -18,8 +18,7 @@ extern "C" RustLinker*
 LLVMRustLinkerNew(LLVMModuleRef DstRef) {
   Module *Dst = unwrap(DstRef);
 
-  auto Ret = std::make_unique<RustLinker>(*Dst);
-  return Ret.release();
+  return new RustLinker(*Dst);
 }
 
 extern "C" void

src/rustllvm/PassWrapper.cpp

@@ -863,7 +863,11 @@ LLVMRustCreateThinLTOData(LLVMRustThinLTOModule *modules,
                           int num_modules,
                           const char **preserved_symbols,
                           int num_symbols) {
+#if LLVM_VERSION_GE(10, 0)
   auto Ret = std::make_unique<LLVMRustThinLTOData>();
+#else
+  auto Ret = llvm::make_unique<LLVMRustThinLTOData>();
+#endif
 
   // Load each module's summary and merge it into one combined index
   for (int i = 0; i < num_modules; i++) {
@@ -1105,7 +1109,11 @@ struct LLVMRustThinLTOBuffer {
 
 extern "C" LLVMRustThinLTOBuffer*
 LLVMRustThinLTOBufferCreate(LLVMModuleRef M) {
+#if LLVM_VERSION_GE(10, 0)
   auto Ret = std::make_unique<LLVMRustThinLTOBuffer>();
+#else
+  auto Ret = llvm::make_unique<LLVMRustThinLTOBuffer>();
+#endif
   {
     raw_string_ostream OS(Ret->data);
     {

src/rustllvm/RustWrapper.cpp

@@ -1477,7 +1477,11 @@ struct LLVMRustModuleBuffer {
 
 extern "C" LLVMRustModuleBuffer*
 LLVMRustModuleBufferCreate(LLVMModuleRef M) {
+#if LLVM_VERSION_GE(10, 0)
   auto Ret = std::make_unique<LLVMRustModuleBuffer>();
+#else
+  auto Ret = llvm::make_unique<LLVMRustModuleBuffer>();
+#endif
   {
     raw_string_ostream OS(Ret->data);
     {