OrcMCJITReplacement.h revision 341825 
1//===---- OrcMCJITReplacement.h - Orc-based MCJIT replacement ---*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file forces OrcMCJITReplacement to link in on certain operating systems.
11// (Windows).
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_EXECUTIONENGINE_ORCMCJITREPLACEMENT_H
16#define LLVM_EXECUTIONENGINE_ORCMCJITREPLACEMENT_H
17
18#include "llvm/ExecutionEngine/ExecutionEngine.h"
19#include <cstdlib>
20
21extern "C" void LLVMLinkInOrcMCJITReplacement();
22
23namespace {
24  struct ForceOrcMCJITReplacementLinking {
25    ForceOrcMCJITReplacementLinking() {
26      // We must reference OrcMCJITReplacement in such a way that compilers will
27      // not delete it all as dead code, even with whole program optimization,
28      // yet is effectively a NO-OP. As the compiler isn't smart enough to know
29      // that getenv() never returns -1, this will do the job.
30      if (std::getenv("bar") != (char*) -1)
31        return;
32
33      LLVMLinkInOrcMCJITReplacement();
34    }
35  } ForceOrcMCJITReplacementLinking;
36}
37
38#endif
39