Index: test/Transforms/MergeFunc/intrinsics.ll
===================================================================
--- /dev/null
+++ test/Transforms/MergeFunc/intrinsics.ll
@@ -0,0 +1,35 @@
+; RUN: opt -S -mergefunc -stats < %s 2>&1 | FileCheck %s
+; This used to crash because mergefunc created a bitcast of an intrinsic.
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+declare i64 @llvm.bswap.i64(i64) unnamed_addr nounwind readnone
+declare i8* @breaker(i8*) unnamed_addr
+
+; @bswap_caller and @collider have the same hash in mergefunc and get fed to
+; enumerate, which used to create a bitcast of the bswap intrinsic that
+; survived on the intrinsics uselist and made the verify pass complain.
+; The repeated calls are just to make the functions large enough to be merged
+; and test that they aren't merged, regardless of the above bug.
+define void @bswap_caller(i64) unnamed_addr {
+; CHECK-LABEL: @bswap_caller(
+entry-block:
+  call i64 @llvm.bswap.i64(i64 %0)
+  call i64 @llvm.bswap.i64(i64 %0)
+  call i64 @llvm.bswap.i64(i64 %0)
+  call i64 @llvm.bswap.i64(i64 %0)
+  ret void
+}
+
+define internal void @collider(i8*) unnamed_addr {
+; CHECK-LABEL: @collider(
+entry-block:
+  call i8* @breaker(i8* %0)
+  call i8* @breaker(i8* %0)
+  call i8* @breaker(i8* %0)
+  call i8* @breaker(i8* %0)
+  ret void
+}
+
+; CHECK-NOT: functions merged