--- a/yaml/simulator.yaml
+++ b/yaml/simulator.yaml
@@ -28,6 +28,7 @@
              -LDFLAGS '-Wl,--no-as-needed'
              -CFLAGS '--std=c99 -fno-extended-identifiers'
              -Mdir=<out>/vcs_simv.csrc
+             -Xcflags='-Wno-error=implicit-function-declaration -Wno-error=int-conversion'
              -o <out>/vcs_simv <cmp_opts> <cov_opts> "
     cov_opts: >
       -cm_dir <out>/test.vdb
