Index: lib/CodeGen/CGExpr.cpp
===================================================================
--- lib/CodeGen/CGExpr.cpp
+++ lib/CodeGen/CGExpr.cpp
@@ -27,6 +27,7 @@
 #include "llvm/ADT/Hashing.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/IR/DataLayout.h"
+#include "llvm/IR/InlineAsm.h"
 #include "llvm/IR/Intrinsics.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/MDBuilder.h"
@@ -2534,21 +2535,29 @@
 
 void CodeGenFunction::EmitTrapCheck(llvm::Value *Checked) {
   llvm::BasicBlock *Cont = createBasicBlock("cont");
-
+  llvm::InlineAsm *EmptyAsm = llvm::InlineAsm::get(llvm::FunctionType::get(CGM.VoidTy, false), 
+						   StringRef(""), StringRef(""), true);
+  // Collapsing all calls to trap down to one per function makes debugging
+  // these issues much more difficult. Eliminating this optimization for now,
+  // with the thought that control by either a debug flag or tying it to an 
+  // optimization level/sanitizer may be a decent path for the future.
+  // RE: Bug: 25682
   // If we're optimizing, collapse all calls to trap down to just one per
   // function to save on code size.
-  if (!CGM.getCodeGenOpts().OptimizationLevel || !TrapBB) {
-    TrapBB = createBasicBlock("trap");
-    Builder.CreateCondBr(Checked, Cont, TrapBB);
-    EmitBlock(TrapBB);
-    llvm::CallInst *TrapCall = EmitTrapCall(llvm::Intrinsic::trap);
-    TrapCall->setDoesNotReturn();
-    TrapCall->setDoesNotThrow();
-    Builder.CreateUnreachable();
-  } else {
-    Builder.CreateCondBr(Checked, Cont, TrapBB);
-  }
-
+  //  if (!CGM.getCodeGenOpts().OptimizationLevel || !TrapBB) {
+  TrapBB = createBasicBlock("trap");
+  Builder.CreateCondBr(Checked, Cont, TrapBB);
+  EmitBlock(TrapBB);
+  llvm::CallInst *TrapCall = EmitTrapCall(llvm::Intrinsic::trap);
+  TrapCall->setDoesNotReturn();
+  TrapCall->setDoesNotThrow();
+  Builder.CreateUnreachable();
+  //} else {
+  //Builder.CreateCondBr(Checked, Cont, TrapBB);
+  //}
+  //this stops the trap calls from being merged at the end of the function
+  Builder.CreateCall(EmptyAsm, {});
+  
   EmitBlock(Cont);
 }