diff --git a/bolt/include/bolt/Core/BinaryFunction.h b/bolt/include/bolt/Core/BinaryFunction.h
index 51b139a15e1a0..aea418034709f 100644
--- a/bolt/include/bolt/Core/BinaryFunction.h
+++ b/bolt/include/bolt/Core/BinaryFunction.h
@@ -650,7 +650,8 @@ class BinaryFunction {
   ///
   /// Prefer to use BinaryContext::getFunctionForSymbol(EntrySymbol, &ID)
   /// instead of calling this function directly.
-  uint64_t getEntryIDForSymbol(const MCSymbol *EntrySymbol) const;
+  std::optional<uint64_t>
+  getEntryIDForSymbol(const MCSymbol *EntrySymbol) const;
 
   /// If the function represents a secondary split function fragment, set its
   /// parent fragment to \p BF.
diff --git a/bolt/lib/Core/BinaryContext.cpp b/bolt/lib/Core/BinaryContext.cpp
index 72c72bbaf4a65..9630f7d4a8872 100644
--- a/bolt/lib/Core/BinaryContext.cpp
+++ b/bolt/lib/Core/BinaryContext.cpp
@@ -2374,8 +2374,15 @@ BinaryFunction *BinaryContext::getFunctionForSymbol(const MCSymbol *Symbol,
     return nullptr;
 
   BinaryFunction *BF = BFI->second;
-  if (EntryDesc)
-    *EntryDesc = BF->getEntryIDForSymbol(Symbol);
+  if (EntryDesc) {
+    const uint64_t Address = BF->getAddress() + Symbol->getOffset();
+    if (BF->isInConstantIsland(Address)) {
+      this->outs() << "BOLT-WARNING: symbol " << Symbol->getName()
+                   << " is in data region of function " << BF->getOneName()
+                   << "(0x" << Twine::utohexstr(BF->getAddress()) << ").\n";
+    }
+    *EntryDesc = BF->getEntryIDForSymbol(Symbol).value_or(0);
+  }
 
   return BF;
 }
diff --git a/bolt/lib/Core/BinaryFunction.cpp b/bolt/lib/Core/BinaryFunction.cpp
index 578a87dc6c09d..07d0d23dfc9f0 100644
--- a/bolt/lib/Core/BinaryFunction.cpp
+++ b/bolt/lib/Core/BinaryFunction.cpp
@@ -3855,7 +3855,8 @@ MCSymbol *BinaryFunction::getSymbolForEntryID(uint64_t EntryID) {
   return nullptr;
 }
 
-uint64_t BinaryFunction::getEntryIDForSymbol(const MCSymbol *Symbol) const {
+std::optional<uint64_t>
+BinaryFunction::getEntryIDForSymbol(const MCSymbol *Symbol) const {
   if (!isMultiEntry())
     return 0;
 
@@ -3882,8 +3883,7 @@ uint64_t BinaryFunction::getEntryIDForSymbol(const MCSymbol *Symbol) const {
       return NumEntries;
     ++NumEntries;
   }
-
-  llvm_unreachable("symbol not found");
+  return std::nullopt;
 }
 
 bool BinaryFunction::forEachEntryPoint(EntryPointCallbackTy Callback) const {
diff --git a/bolt/test/AArch64/check-symbol-area.s b/bolt/test/AArch64/check-symbol-area.s
new file mode 100644
index 0000000000000..abab547dd7558
--- /dev/null
+++ b/bolt/test/AArch64/check-symbol-area.s
@@ -0,0 +1,36 @@
+// This test checks that when looking for a function corresponding to a
+// symbol, BOLT is not looking through a data area (constant island).
+
+# RUN: llvm-mc -filetype=obj -triple aarch64-unknown-unknown %s -o %t.o
+# RUN: %clang %cflags %t.o -o %t.exe -Wl,-q
+# RUN: llvm-bolt %t.exe -o %t.bolt 2>&1 | FileCheck %s
+
+// Before adding a check for constant islands, BOLT would exit with an error
+// of the form: "symbol not found" and throw an LLVM UNREACHABLE error.
+# CHECK-NOT: symbol not found
+# CHECK-NOT: UNREACHABLE
+
+// Now BOLT throws a warning and does not crash.
+# CHECK: BOLT-WARNING: symbol third_block/1  is in data region of function first_block(0x{{[0-9a-f]+}}).
+
+.text
+.global main
+main:
+        add     x0, x1, x1
+        bl      first_block
+        ret
+
+.global first_block
+$d:
+first_block:
+        add     x0, x1, x1
+        bl      second_block
+        ret
+second_block:
+        add     x0, x1, x1
+        bl      third_block
+        ret
+$x:
+third_block:
+        add     x0, x1, x1
+        ret