diff --git a/llvm/cmake/modules/AddLLVM.cmake b/llvm/cmake/modules/AddLLVM.cmake
--- a/llvm/cmake/modules/AddLLVM.cmake
+++ b/llvm/cmake/modules/AddLLVM.cmake
@@ -726,6 +726,39 @@
     endforeach()
   endif()
 
+  if (${name} IN_LIST LLVM_CUSTOM_BINARIES)
+    if (NOT LLVM_${name}_COMPILER_FLAGS AND NOT LLVM_${name}_SHARED_LINKER_FLAGS AND NOT LLVM_${name}_MODULE_LINKER_FLAGS)
+      message(FATAL_ERROR "At least one of compiler or linker flags must be provided when specifying LLVM_CUSTOM_BINARIES")
+    else()
+      if (LLVM_${name}_COMPILER_FLAGS)
+        message(STATUS "Applying ${LLVM_${name}_COMPILER_FLAGS} to ${name}")
+        target_compile_options(${name} PRIVATE ${LLVM_${name}_COMPILER_FLAGS})
+        # For binaries that link with static libraries, recursively apply the flag to those targets.
+        get_target_property(target_libraries ${name} LINK_LIBRARIES)
+        foreach(lib ${target_libraries})
+          if(TARGET ${lib})
+            message(STATUS "Applying ${LLVM_${name}_COMPILER_FLAGS} to ${lib}")
+            target_compile_options(${lib} PRIVATE ${LLVM_${name}_COMPILER_FLAGS})
+          else()
+            message(STATUS "Target ${lib} does not exist in the project. Skipping...")
+          endif()
+        endforeach()
+      endif()
+      if (ARG_SHARED)
+        if (LLVM_${name}_SHARED_LINKER_FLAGS)
+          message(STATUS "Applying ${LLVM_${name}_SHARED_LINKER_FLAGS} to ${name}")
+          target_link_options(${name} PRIVATE ${LLVM_${name}_SHARED_LINKER_FLAGS})
+        endif()
+      endif()
+      if (ARG_MODULE)
+        if (LLVM_${name}_MODULE_LINKER_FLAGS)
+          message(STATUS "Applying ${LLVM_${name}_MODULE_LINKER_FLAGS} to ${name}")
+          target_link_options(${name} PRIVATE ${LLVM_${name}_MODULE_LINKER_FLAGS})
+        endif()
+      endif()
+    endif()
+  endif()
+
   if(ARG_SHARED OR ARG_MODULE)
     llvm_externalize_debuginfo(${name})
     llvm_codesign(${name} ENTITLEMENTS ${ARG_ENTITLEMENTS} BUNDLE_PATH ${ARG_BUNDLE_PATH})
@@ -1019,6 +1052,31 @@
     endforeach()
   endif( LLVM_COMMON_DEPENDS )
 
+  if (${name} IN_LIST LLVM_CUSTOM_BINARIES)
+    if (NOT LLVM_${name}_COMPILER_FLAGS AND NOT LLVM_${name}_EXE_LINKER_FLAGS)
+      message(FATAL_ERROR "At least one of compiler or linker flags must be provided when specifying LLVM_CUSTOM_BINARIES")
+    else()
+      if (LLVM_${name}_COMPILER_FLAGS)
+        message(STATUS "Applying ${LLVM_${name}_COMPILER_FLAGS} to ${name}")
+        target_compile_options(${name} PRIVATE ${LLVM_${name}_COMPILER_FLAGS})
+        # For binaries that link with static libraries, recursively apply the flag to those targets.
+        get_target_property(target_libraries ${name} LINK_LIBRARIES)
+        foreach(lib ${target_libraries})
+          if(TARGET ${lib})
+            message(STATUS "Applying ${LLVM_${name}_COMPILER_FLAGS} to ${lib}")
+            target_compile_options(${lib} PRIVATE ${LLVM_${name}_COMPILER_FLAGS})
+          else()
+            message(STATUS "Target ${lib} does not exist in the project. Skipping...")
+          endif()
+        endforeach()
+      endif()
+      if (LLVM_${name}_EXE_LINKER_FLAGS)
+        message(STATUS "Applying ${LLVM_${name}_EXE_LINKER_FLAGS} to ${name}")
+        target_link_options(${name} PRIVATE ${LLVM_${name}_EXE_LINKER_FLAGS})
+      endif()
+    endif()
+  endif()
+
   if(NOT ARG_IGNORE_EXTERNALIZE_DEBUGINFO)
     llvm_externalize_debuginfo(${name})
   endif()