diff --git a/tests/cbmc/proofs/Makefile.common b/tests/cbmc/proofs/Makefile.common
index ce5315c5533..f20af6b6cf1 100644
--- a/tests/cbmc/proofs/Makefile.common
+++ b/tests/cbmc/proofs/Makefile.common
@@ -299,7 +299,7 @@ CHECKFLAGS += $(CBMC_FLAG_UNSIGNED_OVERFLOW_CHECK)
 NONDET_STATIC ?=
 
 # Flags to pass to goto-cc for compilation and linking
-COMPILE_FLAGS ?= -Wall
+COMPILE_FLAGS ?= -Wall -Werror
 LINK_FLAGS ?= -Wall
 EXPORT_FILE_LOCAL_SYMBOLS ?= --export-file-local-symbols