diff --git a/bolt/lib/Core/BinaryFunction.cpp b/bolt/lib/Core/BinaryFunction.cpp
--- a/bolt/lib/Core/BinaryFunction.cpp
+++ b/bolt/lib/Core/BinaryFunction.cpp
@@ -1860,6 +1860,40 @@
   if (HasFixedIndirectBranch)
     return false;
 
+  // Validate that all data references to function offsets are claimed by
+  // recognized jump tables. Register externally referenced blocks as entry
+  // points.
+  if (!opts::StrictMode && hasInternalReference()) {
+    SmallPtrSet<MCSymbol *, 4> JTTargets;
+    for (const JumpTable *JT : llvm::make_second_range(JumpTables))
+      JTTargets.insert(JT->Entries.begin(), JT->Entries.end());
+
+    bool UnclaimedReference = false;
+    for (uint64_t Destination : ExternallyReferencedOffsets) {
+      // Ignore __builtin_unreachable().
+      if (Destination == getSize())
+        continue;
+
+      if (BinaryBasicBlock *BB = getBasicBlockAtOffset(Destination)) {
+        bool Found = JTTargets.contains(BB->getLabel());
+        if (Found)
+          continue;
+
+        if (opts::Verbosity >= 1) {
+          outs() << "BOLT-WARNING: unclaimed data to code reference (possibly "
+                 << "an unrecognized jump table entry) to " << BB->getName()
+                 << " in " << *this << ".\n";
+        }
+      } else if (opts::Verbosity >= 1) {
+        outs() << "BOLT-WARNING: unknown data to code reference to offset "
+               << Twine::utohexstr(Destination) << " in " << *this << ".\n";
+      }
+      UnclaimedReference = true;
+    }
+    if (UnclaimedReference)
+      return false;
+  }
+
   if (HasUnknownControlFlow && !BC.HasRelocations)
     return false;
 
diff --git a/bolt/test/X86/unclaimed-jt-entries.s b/bolt/test/X86/unclaimed-jt-entries.s
new file mode 100644
--- /dev/null
+++ b/bolt/test/X86/unclaimed-jt-entries.s
@@ -0,0 +1,66 @@
+# This test ensures that "unclaimed" jump table entries are accounted later
+# in postProcessIndirectBranches and the function is marked as non-simple.
+
+# The test is compiled from the following source using GCC 12.2 -O3:
+# https://godbolt.org/z/YcPG131s6
+# int func(long long Input) {
+#   switch(Input) {
+#   case 3: return 1;
+#   case 4: return 2;
+#   case 6: return 3;
+#   case 8: return 4;
+#   case 13: return 5;
+#   default: __builtin_unreachable();
+#   }
+# }
+
+# REQUIRES: system-linux
+
+# RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown %s -o %t.o
+# RUN: %clang %cflags -no-pie %t.o -o %t.exe -Wl,-q
+# RUN: llvm-bolt %t.exe -v=1 -o %t.out |& FileCheck %s
+
+# CHECK: BOLT-WARNING: unclaimed data to code reference (possibly an unrecognized jump table entry) to .Ltmp[[#]] in main
+# CHECK: BOLT-WARNING: unclaimed data to code reference (possibly an unrecognized jump table entry) to .Ltmp[[#]] in main
+# CHECK: BOLT-WARNING: unclaimed data to code reference (possibly an unrecognized jump table entry) to .Ltmp[[#]] in main
+# CHECK: BOLT-WARNING: unclaimed data to code reference (possibly an unrecognized jump table entry) to .Ltmp[[#]] in main
+# CHECK: BOLT-WARNING: unclaimed data to code reference (possibly an unrecognized jump table entry) to .Ltmp[[#]] in main
+# CHECK: BOLT-WARNING: failed to post-process indirect branches for main
+
+  .text
+  .globl main
+  .type main, %function
+  .size main, .Lend-main
+main:
+  jmp *L4-24(,%rdi,8)
+.L5:
+  movl $4, %eax
+  ret
+.L9:
+  movl $2, %eax
+  ret
+.L8:
+  movl $1, %eax
+  ret
+.L3:
+  movl $5, %eax
+  ret
+.L6:
+  movl $3, %eax
+  ret
+.Lend:
+
+.section .rodata
+  .globl L4
+L4:
+  .quad .L8
+  .quad .L9
+  .quad .L3
+  .quad .L6
+  .quad .L3
+  .quad .L5
+  .quad .L3
+  .quad .L3
+  .quad .L3
+  .quad .L3
+  .quad .L3