Index: lld/MachO/UnwindInfoSection.cpp
===================================================================
--- lld/MachO/UnwindInfoSection.cpp
+++ lld/MachO/UnwindInfoSection.cpp
@@ -568,8 +568,10 @@
     l2PagesOffset += SECOND_LEVEL_PAGE_BYTES;
   }
   // Level-1 sentinel
-  const CompactUnwindEntry<Ptr> &cuEnd = cuVector.back();
-  iep->functionOffset = cuEnd.functionAddress + cuEnd.functionLength;
+  const CompactUnwindEntry<Ptr> &cuEnd = *cuPtrVector.back();
+  assert(cuEnd.functionAddress != static_cast<Ptr>(UINT64_MAX));
+  iep->functionOffset =
+      cuEnd.functionAddress - in.header->addr + cuEnd.functionLength;
   iep->secondLevelPagesSectionOffset = 0;
   iep->lsdaIndexArraySectionOffset =
       lsdaOffset +
Index: lld/test/MachO/compact-unwind.s
===================================================================
--- lld/test/MachO/compact-unwind.s
+++ lld/test/MachO/compact-unwind.s
@@ -43,10 +43,14 @@
 # CHECK:        Personality functions: (count = 2)
 # CHECK-DAG:     personality[{{[0-9]+}}]: 0x{{0*}}[[#MY_PERSONALITY-BASE]]
 # CHECK-DAG:     personality[{{[0-9]+}}]: 0x{{0*}}[[#GXX_PERSONALITY-BASE]]
+# CHECK:      Top level indices: (count = 2)
+# CHECK-DAG:    [0]: function offset={{.*}}, 2nd level page offset=[[#%x,PAGEOFF:]], LSDA offset=
+# CHECK-DAG:    [1]: function offset={{.*}}, 2nd level page offset=0x00000000, LSDA offset=
 # CHECK:        LSDA descriptors:
 # CHECK-DAG:     function offset=0x[[#%.8x,FOO-BASE]],  LSDA offset=0x[[#%.8x,EXCEPTION0-BASE]]
 # CHECK-DAG:     function offset=0x[[#%.8x,MAIN-BASE]], LSDA offset=0x[[#%.8x,EXCEPTION1-BASE]]
 # CHECK:        Second level indices:
+# CHECK-NEXT:   Second level index[0]: offset in section={{.*}}, base function offset=0x[[#.8x,PAGEOFF]]
 # CHECK-DAG:     function offset=0x[[#%.8x,MAIN-BASE]], encoding
 # CHECK-DAG:     function offset=0x[[#%.8x,FOO-BASE]], encoding
 # CHECK-DAG:     function offset=0x[[#%.8x,BAZ-BASE]], encoding