# added --enable-gcc-warnings (not for user consumption).

configure.in

@@ -16,6 +16,29 @@ AM_PROG_CC_STDC
 AC_PROG_INSTALL
 AC_PROG_RANLIB
 
+AC_ARG_ENABLE(gcc-warnings,
+[  --enable-gcc-warnings   turn on lots of GCC warnings (not recommended)],
+[case "${enableval}" in
+   yes|no) ;;
+   *)      AC_MSG_ERROR([bad value ${enableval} for gcc-warnings option]) ;;
+ esac
+],
+enableval=no
+)
+if test "${enableval}" = yes; then
+  BISON_WARNING(-Wall)
+  BISON_WARNING(-W)
+  BISON_WARNING(-Wbad-function-cast)
+  BISON_WARNING(-Wcast-align)
+  BISON_WARNING(-Wcast-qual)
+  BISON_WARNING(-Wmissing-declarations)
+  BISON_WARNING(-Wmissing-prototypes)
+  BISON_WARNING(-Wnested-externs)
+  BISON_WARNING(-Wno-char-subscripts)
+  BISON_WARNING(-Wstrict-prototypes)
+  BISON_WARNING(-Wwrite-strings)
+fi
+
 dnl Checks for libraries.
 
 dnl Checks for header files.