--- nono/configure.ac	2026/04/29 17:05:07	1.1.1.10
+++ nono/configure.ac	2026/04/29 17:05:11	1.1.1.11
@@ -54,6 +54,7 @@ AC_DEFUN([ADD_CC_WARN_IF],[
 	CFLAGS="${CFLAGS} -Werror $1"
 	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [])],
 		AC_MSG_RESULT([yes])
+		eval `echo cc_has$1=yes | sed -e 's/-/_/g'`
 		WARNFLAGS_C="${WARNFLAGS_C} $1",
 		AC_MSG_RESULT([no]))
 	CFLAGS="${old_CFLAGS}"
@@ -63,6 +64,11 @@ ADD_CC_WARN_IF(-Wextra-semi)
 ADD_CC_WARN_IF(-Wlogical-op)
 ADD_CC_WARN_IF(-Wmissing-prototypes)
 ADD_CC_WARN_IF(-Wmissing-variable-declarations)
+# -Wshadow-local があればそっちを使う(gcc>=7)、なければ -Wshadow (clang)
+ADD_CC_WARN_IF(-Wshadow-local)
+if test x"${cc_has_Wshadow_local}" != xyes; then
+	ADD_CC_WARN_IF(-Wshadow)
+fi
 AC_LANG_POP([C])
 AC_SUBST([WARNFLAGS_C])
 
@@ -75,6 +81,7 @@ AC_DEFUN([ADD_CXX_WARN_IF],[
 	CXXFLAGS="${CXXFLAGS} -Werror $1"
 	AC_COMPILE_IFELSE([AC_LANG_PROGRAM([], [])],
 		AC_MSG_RESULT([yes])
+		eval `echo cxx_has$1=yes | sed -e 's/-/_/g'`
 		WARNFLAGS_CXX="${WARNFLAGS_CXX} $1",
 		AC_MSG_RESULT([no]))
 	CXXFLAGS="${old_CXXFLAGS}"
@@ -86,6 +93,11 @@ ADD_CXX_WARN_IF(-Winconsistent-missing-d
 ADD_CXX_WARN_IF(-Wlogical-op)
 ADD_CXX_WARN_IF(-Wmissing-prototypes)
 ADD_CXX_WARN_IF(-Wmissing-variable-declarations)
+# -Wshadow-local があればそっちを使う(gcc>=7)、なければ -Wshadow (clang)
+ADD_CXX_WARN_IF(-Wshadow-local)
+if test x"${cxx_has_Wshadow_local}" != xyes; then
+	ADD_CXX_WARN_IF(-Wshadow)
+fi
 ADD_CXX_WARN_IF(-Wvla-extension)
 AC_SUBST([WARNFLAGS_CXX])