Hi Rodrigo, Regarding this issue[1], I have found couple of ways to address this: The easiest way is to do AC_PROG_CXX before AC_PROG_CC: --- a/configure.ac Sat Oct 5 13:15:28 2024 +++ b/configure.ac Sat Oct 5 13:15:48 2024 @@ -124,8 +124,8 @@ if test "x$enable_ssl" != "x"; then AC_MSG_ERROR([The flag --enable-ssl is deprecated, use --enable-tls]) fi -AC_PROG_CC AC_PROG_CXX +AC_PROG_CC AC_PROG_RANLIB AC_PROG_CPP Which now errors out when no working compiler is found: 'configure: error: C++ compiler cannot create executables' Alternately, we can add a check to verify if the complier actually exists, and if not, exit. Something like this: dnl ------------------------------------------------------------ dnl AC_PROG_CXX will set CXX=g++ even if it finds no useable C++ dnl compiler, so we have to check whether the program named by dnl CXX exists. dnl ------------------------------------------------------------ dnl AC_PROG_CXX AC_PATH_PROG(REAL_CXX, $CXX) HAVE_CXX=no if test -n "$REAL_CXX"; then HAVE_CXX=yes fi if HAVE_CXX="no"; then echo "Error: No working C++ compiler found!" exit 1 fi If either of these solutions work for you, I can create a pull request. [1] https://github.com/dillo-browser/dillo/issues/187 Regards, Alex