- dnl It would be so nice if plus signs were supported in AC_ARG_ENABLE.
- dnl Feature request submitted on 2010-03-13.
- m4_ifdef([gl_CXX_CHOICE_DEFAULT_NO],
- [AC_ARG_ENABLE([cxx],
- [ --enable-cxx also build C++ sources],
- [CXX_CHOICE="$enableval"],
- [CXX_CHOICE=no])],
- [AC_ARG_ENABLE([cxx],
- [ --disable-cxx do not build C++ sources],
- [CXX_CHOICE="$enableval"],
- [CXX_CHOICE=yes])])
+ dnl Plus signs are supported in AC_ARG_ENABLE starting with autoconf-2.66.
+ m4_version_prereq([2.66],
+ [m4_ifdef([gl_CXX_CHOICE_DEFAULT_NO],
+ [AC_ARG_ENABLE([c++],
+ [ --enable-c++ also build C++ sources],
+ [CXX_CHOICE="$enableval"],
+ [CXX_CHOICE=no])],
+ [AC_ARG_ENABLE([c++],
+ [ --disable-c++ do not build C++ sources],
+ [CXX_CHOICE="$enableval"],
+ [CXX_CHOICE=yes])])],
+ [m4_ifdef([gl_CXX_CHOICE_DEFAULT_NO],
+ [AC_ARG_ENABLE([cxx],
+ [ --enable-cxx also build C++ sources],
+ [CXX_CHOICE="$enableval"],
+ [CXX_CHOICE=no])],
+ [AC_ARG_ENABLE([cxx],
+ [ --disable-cxx do not build C++ sources],
+ [CXX_CHOICE="$enableval"],
+ [CXX_CHOICE=yes])])])