diff --git a/src/OpenGL/libGLESv2/Program.cpp b/src/OpenGL/libGLESv2/Program.cpp
index cc4c49c..eb1070e 100644
--- a/src/OpenGL/libGLESv2/Program.cpp
+++ b/src/OpenGL/libGLESv2/Program.cpp
@@ -1454,7 +1454,7 @@
 			}
 
 			bool found = false;
-			for(const glsl::Varying varying : vertexShader->varyings)
+			for(const glsl::Varying& varying : vertexShader->varyings)
 			{
 				if(tfVaryingName == varying.name)
 				{
diff --git a/third_party/llvm-7.0/llvm/lib/CodeGen/InlineSpiller.cpp b/third_party/llvm-7.0/llvm/lib/CodeGen/InlineSpiller.cpp
index 007e928..d88df6a 100644
--- a/third_party/llvm-7.0/llvm/lib/CodeGen/InlineSpiller.cpp
+++ b/third_party/llvm-7.0/llvm/lib/CodeGen/InlineSpiller.cpp
@@ -1396,7 +1396,7 @@
   }
   // For spills in SpillsToKeep with LiveReg set (i.e., not original spill),
   // save them to SpillsToIns.
-  for (const auto Ent : SpillsToKeep) {
+  for (const auto& Ent : SpillsToKeep) {
     if (Ent.second)
       SpillsToIns[Ent.first->getBlock()] = Ent.second;
   }
@@ -1470,7 +1470,7 @@
                                      StackIntvl.getValNumInfo(0));
 
     // Insert hoisted spills.
-    for (auto const Insert : SpillsToIns) {
+    for (auto const& Insert : SpillsToIns) {
       MachineBasicBlock *BB = Insert.first;
       unsigned LiveReg = Insert.second;
       MachineBasicBlock::iterator MI = IPA.getLastInsertPointIter(OrigLI, *BB);
diff --git a/third_party/llvm-7.0/llvm/lib/IR/Attributes.cpp b/third_party/llvm-7.0/llvm/lib/IR/Attributes.cpp
index d871874..8a9811e 100644
--- a/third_party/llvm-7.0/llvm/lib/IR/Attributes.cpp
+++ b/third_party/llvm-7.0/llvm/lib/IR/Attributes.cpp
@@ -929,7 +929,7 @@
     MaxIndex = Attrs[Attrs.size() - 2].first;
 
   SmallVector<AttributeSet, 4> AttrVec(attrIdxToArrayIdx(MaxIndex) + 1);
-  for (const auto Pair : Attrs)
+  for (const auto& Pair : Attrs)
     AttrVec[attrIdxToArrayIdx(Pair.first)] = Pair.second;
 
   return getImpl(C, AttrVec);