diff --git a/src/libAtomVM/CMakeLists.txt b/src/libAtomVM/CMakeLists.txt
index 0aa1eba95f..60731eff0a 100644
--- a/src/libAtomVM/CMakeLists.txt
+++ b/src/libAtomVM/CMakeLists.txt
@@ -132,9 +132,9 @@ add_library(libAtomVM ${SOURCE_FILES} ${HEADER_FILES})
 target_include_directories(libAtomVM PUBLIC ${CMAKE_CURRENT_SOURCE_DIR})
 target_compile_features(libAtomVM PUBLIC c_std_11)
 if (CMAKE_C_COMPILER_ID STREQUAL "GNU")
-    target_compile_options(libAtomVM PUBLIC -Wall ${MAYBE_PEDANTIC_FLAG} ${MAYBE_WERROR_FLAG} -Wextra -ggdb -Werror=incompatible-pointer-types)
+    target_compile_options(libAtomVM PUBLIC -Wall ${MAYBE_PEDANTIC_FLAG} ${MAYBE_WERROR_FLAG} -Wextra -ggdb -Werror=incompatible-pointer-types -Wswitch-enum)
 elseif (CMAKE_C_COMPILER_ID MATCHES "Clang")
-    target_compile_options(libAtomVM PUBLIC -Wall ${MAYBE_PEDANTIC_FLAG} -Wno-gnu-zero-variadic-macro-arguments --extra-warnings -Werror=incompatible-pointer-types ${MAYBE_WERROR_FLAG} -g)
+    target_compile_options(libAtomVM PUBLIC -Wall ${MAYBE_PEDANTIC_FLAG} -Wno-gnu-zero-variadic-macro-arguments --extra-warnings -Werror=incompatible-pointer-types -Wswitch-enum ${MAYBE_WERROR_FLAG} -g)
 endif()
 
 if (ENABLE_REALLOC_GC)
diff --git a/src/libAtomVM/term.c b/src/libAtomVM/term.c
index 4b55b1df54..9fc3d29645 100644
--- a/src/libAtomVM/term.c
+++ b/src/libAtomVM/term.c
@@ -1024,6 +1024,11 @@ TermCompareResult term_compare(term t, term other, TermCompareOpts opts, GlobalC
                             break;
                         }
                     }
+                    case TERM_TYPE_INDEX_NIL:
+                        // This cannot happen, since this branch is executed only when
+                        // `type_t == type_other`,
+                        // but we do `t == other` as the first thing, making this case unreachable.
+                    case TERM_TYPE_INDEX_INVALID:
                     default:
                         UNREACHABLE();
                 }