Try to conditional link the pref lib

CMakeLists.txt

@@ -279,6 +279,10 @@ if(CMAKE_PROJECT_NAME STREQUAL PROJECT_NAME)
   # endforeach(arch)
 
 
+  set(CONDITIONAL_COMPONENTS "")
+  if(LLVM_USE_PERF)
+    list(APPEND CONDITIONAL_COMPONENTS PerfJITEvents)
+  endif()
   llvm_map_components_to_libnames(llvm_libs
     core
     support
@@ -289,6 +293,7 @@ if(CMAKE_PROJECT_NAME STREQUAL PROJECT_NAME)
     # x86asmparser
     # x86codegen
     ExecutionEngine
+    ${CONDITIONAL_COMPONENTS}
     ${LLVM_TARGETS_TO_BUILD}
     )
 

libserene/lib/jit/halley.cpp

@@ -106,13 +106,9 @@ Halley::Halley(std::unique_ptr<SereneContext> ctx,
 
                       ? llvm::JITEventListener::createGDBRegistrationListener()
                       : nullptr),
-      perfListener(
-// TODO: [llvm] Remove this line when apt.llvm.org fixed the undefined symbol
-//       for createPerfJITEventListener
-#define LLVM_USE_PERF 0
-          ctx->opts.JITenablePerfNotificationListener
-              ? llvm::JITEventListener::createPerfJITEventListener()
-              : nullptr),
+      perfListener(ctx->opts.JITenablePerfNotificationListener
+                       ? llvm::JITEventListener::createPerfJITEventListener()
+                       : nullptr),
       jtmb(jtmb), dl(dl), ctx(std::move(ctx)){};
 
 // MaybeJITPtr Halley::lookup(exprs::Symbol &sym) const {