diff --git a/CMakeLists.txt b/CMakeLists.txt
index e6e9ed2..a3152d3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -96,6 +96,15 @@ include_directories(src)
 
 find_package(weaseljson REQUIRED)
 
+# Suppress deprecated literal operator warnings globally (from nlohmann_json and
+# toml11)
+if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+  add_compile_options(-Wno-unknown-warning-option
+                      -Wno-deprecated-literal-operator)
+elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+  # GCC doesn't have deprecated-literal-operator warning, so no need to suppress
+endif()
+
 # Generate JSON token hash table using gperf
 find_program(GPERF_EXECUTABLE gperf REQUIRED)
 add_custom_command(