diff --git a/llvm/lib/Analysis/StackLifetime.cpp b/llvm/lib/Analysis/StackLifetime.cpp
--- a/llvm/lib/Analysis/StackLifetime.cpp
+++ b/llvm/lib/Analysis/StackLifetime.cpp
@@ -257,14 +257,12 @@
       unsigned AllocaNo = It.second.AllocaNo;
 
       if (IsStart) {
-        assert(!Started.test(AllocaNo) || Start[AllocaNo] == BBStart);
         if (!Started.test(AllocaNo)) {
           Started.set(AllocaNo);
           Ended.reset(AllocaNo);
           Start[AllocaNo] = InstNo;
         }
       } else {
-        assert(!Ended.test(AllocaNo));
         if (Started.test(AllocaNo)) {
           LiveRanges[AllocaNo].addRange(Start[AllocaNo], InstNo);
           Started.reset(AllocaNo);
diff --git a/llvm/test/Analysis/StackSafetyAnalysis/lifetime.ll b/llvm/test/Analysis/StackSafetyAnalysis/lifetime.ll
--- a/llvm/test/Analysis/StackSafetyAnalysis/lifetime.ll
+++ b/llvm/test/Analysis/StackSafetyAnalysis/lifetime.ll
@@ -924,6 +924,31 @@
   ret void
 }
 
+define void @multiple_start_end() {
+; CHECK-LABEL: define void @multiple_start_end
+entry:
+; CHECK: entry:
+; CHECK-NEXT: Alive: <>
+  %x = alloca i8
+  call void @llvm.lifetime.start.p0i8(i64 1, i8* %x)
+; CHECK: call void @llvm.lifetime.start.p0i8(i64 1, i8* %x)
+; CHECK-NEXT: Alive: <x>
+
+  call void @llvm.lifetime.start.p0i8(i64 1, i8* %x)
+; CHECK: call void @llvm.lifetime.start.p0i8(i64 1, i8* %x)
+; CHECK-NEXT: Alive: <x>
+
+  call void @llvm.lifetime.end.p0i8(i64 1, i8* %x)
+; CHECK: call void @llvm.lifetime.end.p0i8(i64 1, i8* %x)
+; CHECK-NEXT: Alive: <>
+
+  call void @llvm.lifetime.end.p0i8(i64 1, i8* %x)
+; CHECK: call void @llvm.lifetime.end.p0i8(i64 1, i8* %x)
+; CHECK-NEXT: Alive: <>
+
+  ret void
+}
+
 declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture)
 declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture)
 declare void @llvm.lifetime.start.p0i32(i64, i32* nocapture)