+printf "int main(void){return 0;}\n" > minimal.c
+
+WARN_CXXFLAGS=""
+printf "Checking for available C++ compiler warning flags... "
+for flag in -Wall -Wextra -Wwrite-strings -Wswitch-enum; do
+ if ${CC} $flag -o minimal minimal.c > /dev/null 2>&1
+ then
+ WARN_CXXFLAGS="${WARN_CXXFLAGS}${WARN_CXXFLAGS:+ }${flag}"
+ fi
+done
+printf "\n\t${WARN_CXXFLAGS}\n"
+
+WARN_CFLAGS="${WARN_CXXFLAGS}"
+printf "Checking for available C compiler warning flags... "
+for flag in -Wmissing-declarations; do
+ if ${CC} $flag -o minimal minimal.c > /dev/null 2>&1
+ then
+ WARN_CFLAGS="${WARN_CFLAGS}${WARN_CFLAGS:+ }${flag}"
+ fi
+done
+printf "\n\t${WARN_CFLAGS}\n"
+
+rm -f minimal minimal.c
+