diff --git a/llvm/cmake/modules/HandleLLVMOptions.cmake b/llvm/cmake/modules/HandleLLVMOptions.cmake
index c84e2ccab8094..22ecf4dcee368 100644
--- a/llvm/cmake/modules/HandleLLVMOptions.cmake
+++ b/llvm/cmake/modules/HandleLLVMOptions.cmake
@@ -948,6 +948,15 @@ if (LLVM_ENABLE_WARNINGS AND (LLVM_COMPILER_IS_GCC_COMPATIBLE OR CLANG_CL))
   # Enable -Wstring-conversion to catch misuse of string literals.
   if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
     append("-Wstring-conversion" CMAKE_C_FLAGS CMAKE_CXX_FLAGS)
+
+    # Disable -Wno-pass-failed flag, which reports failure to perform
+    # optimizations suggested by pragmas. This warning is not relevant for LLVM
+    # projects and may be injected by pragmas in libstdc++.
+    # FIXME: Reconsider this choice if warnings from STL headers can be reliably
+    # avoided (https://github.com/llvm/llvm-project/issues/157666).
+    # This option has been available since Clang 3.5, and we do require a newer
+    # version.
+    append("-Wno-pass-failed" CMAKE_CXX_FLAGS)
   endif()
 
   if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
@@ -962,13 +971,6 @@ if (LLVM_ENABLE_WARNINGS AND (LLVM_COMPILER_IS_GCC_COMPATIBLE OR CLANG_CL))
 
   # Enable -Wctad-maybe-unsupported to catch unintended use of CTAD.
   add_flag_if_supported("-Wctad-maybe-unsupported" CTAD_MAYBE_UNSPPORTED_FLAG)
-
-  # Disable -Wno-pass-failed flag, which reports failure to perform
-  # optimizations suggested by pragmas. This warning is not relevant for LLVM
-  # projects and may be injected by pragmas in libstdc++.
-  # FIXME: Reconsider this choice if warnings from STL headers can be reliably
-  # avoided (https://github.com/llvm/llvm-project/issues/157666).
-  add_flag_if_supported("-Wno-pass-failed" NO_PASS_FAILED_FLAG)
 endif (LLVM_ENABLE_WARNINGS AND (LLVM_COMPILER_IS_GCC_COMPATIBLE OR CLANG_CL))
 
 if (LLVM_COMPILER_IS_GCC_COMPATIBLE AND NOT LLVM_ENABLE_WARNINGS)