Remove another variable unused in -Asserts build

[oota-llvm.git] / lib / Target / X86 / X86TargetMachine.cpp

diff --git a/lib/Target/X86/X86TargetMachine.cpp b/lib/Target/X86/X86TargetMachine.cpp
index d318244e0f70710ac78b5e32b9eaad3adf36fd19..2e869eb7c3cd6eaf34b0d2b68d8cbae06f5ecab0 100644 (file)
--- a/lib/Target/X86/X86TargetMachine.cpp
+++ b/lib/Target/X86/X86TargetMachine.cpp
@@ -110,6 +110,13 @@ X86TargetMachine::X86TargetMachine(const Target &T, const Triple &TT,
                         OL),
       TLOF(createTLOF(getTargetTriple())),
       Subtarget(TT, CPU, FS, *this, Options.StackAlignmentOverride) {
+  // Windows stack unwinder gets confused when execution flow "falls through"
+  // after a call to 'noreturn' function.
+  // To prevent that, we emit a trap for 'unreachable' IR instructions.
+  // (which on X86, happens to be the 'ud2' instruction)
+  if (Subtarget.isTargetWin64())
+    this->Options.TrapUnreachable = true;
+
   // By default (and when -ffast-math is on), enable estimate codegen for
   // everything except scalar division. By default, use 1 refinement step for
   // all operations. Defaults may be overridden by using command-line options.