From d492fe0a00b4afb99c7ba6292961d6d98698373c Mon Sep 17 00:00:00 2001
From: Alex Crichton <alex@alexcrichton.com>
Date: Tue, 30 Jan 2018 11:53:18 -0800
Subject: [PATCH] rustc: Add some defines for LLVM 7 compat

I was testing out the tip support to see what's going on with wasm, and this was
I believe the only issue encountered with LLVM 7 support so far.
---
 src/rustllvm/PassWrapper.cpp | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/rustllvm/PassWrapper.cpp b/src/rustllvm/PassWrapper.cpp
index b2f1229891d..06d1301d700 100644
--- a/src/rustllvm/PassWrapper.cpp
+++ b/src/rustllvm/PassWrapper.cpp
@@ -836,6 +836,10 @@ struct LLVMRustThinLTOData {
   StringMap<FunctionImporter::ImportMapTy> ImportLists;
   StringMap<FunctionImporter::ExportSetTy> ExportLists;
   StringMap<GVSummaryMapTy> ModuleToDefinedGVSummaries;
+
+#if LLVM_VERSION_GE(7, 0)
+  LLVMRustThinLTOData() : Index(/* isPerformingAnalysis = */ false) {}
+#endif
 };
 
 // Just an argument to the `LLVMRustCreateThinLTOData` function below.
@@ -918,7 +922,14 @@ LLVMRustCreateThinLTOData(LLVMRustThinLTOModule *modules,
   //
   // This is copied from `lib/LTO/ThinLTOCodeGenerator.cpp`
 #if LLVM_VERSION_GE(5, 0)
+#if LLVM_VERSION_GE(7, 0)
+  auto deadIsPrevailing = [&](GlobalValue::GUID G) {
+    return PrevailingType::Unknown;
+  };
+  computeDeadSymbols(Ret->Index, Ret->GUIDPreservedSymbols, deadIsPrevailing);
+#else
   computeDeadSymbols(Ret->Index, Ret->GUIDPreservedSymbols);
+#endif
   ComputeCrossModuleImport(
     Ret->Index,
     Ret->ModuleToDefinedGVSummaries,