diff --git a/ci/config.mk.clang-12.sed b/ci/config.mk.clang-12.sed
index e305c59..810b723 100644
--- a/ci/config.mk.clang-12.sed
+++ b/ci/config.mk.clang-12.sed
@@ -1,3 +1,3 @@
 # Clang 12 (or Apple clang 13) and later makes a warning '-Wcompound-token-split-by-macro' enable by default.
-/^PERL_CFLAGS[[:blank:]]*=/s/$/ -Wno-error=compound-token-split-by-macro/
-/^RUBY_CFLAGS[[:blank:]]*=/s/$/ -Wno-error=compound-token-split-by-macro/
+/^PERL_CFLAGS_EXTRA[[:blank:]]*=/s/$/ -Wno-error=compound-token-split-by-macro/
+/^RUBY_CFLAGS_EXTRA[[:blank:]]*=/s/$/ -Wno-error=compound-token-split-by-macro/
diff --git a/ci/config.mk.clang.sed b/ci/config.mk.clang.sed
index da6044d..9dc271c 100644
--- a/ci/config.mk.clang.sed
+++ b/ci/config.mk.clang.sed
@@ -1,2 +1,2 @@
 /^CFLAGS[[:blank:]]*=/s/$/ -Wno-error=missing-field-initializers/
-/^RUBY_CFLAGS[[:blank:]]*=/s/$/ -Wno-error=unknown-attributes -Wno-error=ignored-attributes/
+/^RUBY_CFLAGS_EXTRA[[:blank:]]*=/s/$/ -Wno-error=unknown-attributes -Wno-error=ignored-attributes/
diff --git a/ci/config.mk.sed b/ci/config.mk.sed
index cd2cd9c..51e7ec9 100644
--- a/ci/config.mk.sed
+++ b/ci/config.mk.sed
@@ -1,2 +1,3 @@
 /^CFLAGS[[:blank:]]*=/s/$/ -Wall -Wextra -Wshadow -Werror/
-/^PERL_CFLAGS[[:blank:]]*=/s/$/ -Wno-error=unused-function/
+/^PERL_CFLAGS_EXTRA[[:blank:]]*=/s/$/ -Wno-error=unused-function/
+/^RUBY_CFLAGS_EXTRA[[:blank:]]*=/s/$/ -Wno-error=unused-parameter/