Hi all ! I have written a so-called terminal for gnuplot [1], based on wxWidgets [2] among other libraries. [1] http://www.gnuplot.info [2] http://www.wxwidgets.org gnuplot is written in C, wxWidgets is a gui library written in C++, and the terminal is supposed to be compiled optionally. I had to add AC_PROG_CXX and AC_PROG_CXXCPP to the configure.in file. As many of you may know, they should not be called conditionally, so the script do call them unconditionally. But, of course, users should still be able to compile gnuplot if they don't have any C++ compiler. In this case, the macro AC_PROG_CXX does not fail, but sets by default CXX to g++, even if it is not present, so that automake will finally think that the project contains some C++ files, and use g++ to link the object files. .... And there it fails. So I did the following : [...] dnl wxWidgets terminal needs C++ dnl These tests cannot be called conditionally. dnl However, even if there is no C++ compiler on the system, dnl autoconf will set CXX as g++ : this must be reverted. AC_PROG_CXX AC_PROG_CXXCPP AC_LANG_PUSH([C++]) AC_MSG_CHECKING(whether $CXX is actually working) AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <iostream>]], [[const char hw[] = "Hello, World\n"; std::cout << hw;]])], [AC_MSG_RESULT([yes]) working_cxx=yes], [AC_MSG_RESULT([no]) working_cxx=no CXX=$CC ]) AC_LANG_POP([C++]) AC_ARG_ENABLE(wxwidgets, [ --disable-wxwidgets wxWidgets terminal (default enabled)], enable_wxwidgets=no, enable_wxwidgets=yes) if test "${enable_wxwidgets}" = yes then dnl variable used to determine if all checks pass enable_wxwidgets_ok=yes dnl Check for the C++ compiler if test "${working_cxx}" = "no"; then AC_MSG_WARN([No C++ compiler found. The wxWidgets terminal will not be compiled.]) enable_wxwidgets_ok=no fi fi [...] Can you comment on this, and tell me if it is sure enough ? It works for me (autoconf 2.59, I tried it by renaming g++ and c++ to somethings else), but I would like to be sure that it will work on future autoconf versions. Or is there a smarter way to do it ? Thank you for the great work done on the autotools. Best regards, Timothée Lecomte _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf
