- //===-- MCJIT.h - MC-Based Just-In-Time Execution Engine --------*- C++ -*-===// 
- // 
- // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 
- // See https://llvm.org/LICENSE.txt for license information. 
- // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 
- // 
- //===----------------------------------------------------------------------===// 
- // 
- // This file forces the MCJIT to link in on certain operating systems. 
- // (Windows). 
- // 
- //===----------------------------------------------------------------------===// 
-   
- #ifndef LLVM_EXECUTIONENGINE_MCJIT_H 
- #define LLVM_EXECUTIONENGINE_MCJIT_H 
-   
- #include "llvm/ExecutionEngine/ExecutionEngine.h" 
- #include <cstdlib> 
-   
- extern "C" void LLVMLinkInMCJIT(); 
-   
- namespace { 
-   struct ForceMCJITLinking { 
-     ForceMCJITLinking() { 
-       // We must reference MCJIT in such a way that compilers will not 
-       // delete it all as dead code, even with whole program optimization, 
-       // yet is effectively a NO-OP. As the compiler isn't smart enough 
-       // to know that getenv() never returns -1, this will do the job. 
-       // This is so that globals in the translation units where these functions 
-       // are defined are forced to be initialized, populating various 
-       // registries. 
-       if (std::getenv("bar") != (char*) -1) 
-         return; 
-   
-       LLVMLinkInMCJIT(); 
-     } 
-   } ForceMCJITLinking; 
- } 
-   
- #endif 
-