[build] Check for python3 command, not python.

PEP 394 does not require the python command to be installed.

diff --git a/configure.ac b/configure.ac
index 0a178069acbc50747d9c1aad73b39183bcd1953f..32ba148517f59130c3a098c16beb5491fdd973b2 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -59,10 +59,10 @@ dnl Check for stuff needed for building the GiNaC interactive shell (ginsh).
 AC_CHECK_HEADERS(unistd.h)
 GINAC_HAVE_RUSAGE
 GINAC_READLINE
-dnl Python is necessary for building function.{cpp,h}
-AC_PATH_PROG(PYTHON, python, "")
-AS_IF([test -z "$PYTHON" -a ! -f "$srcdir/ginac/function.cpp"],
-      [AC_MSG_ERROR([GiNaC will not compile because Python is missing])])
+dnl Python3 is necessary for building function.{cpp,h}
+AC_PATH_PROG(PYTHON3, python3, "")
+AS_IF([test -z "$PYTHON3" -a ! -f "$srcdir/ginac/function.cpp"],
+      [AC_MSG_ERROR([GiNaC will not compile because Python3 is missing])])
 
 dnl Check for dl library (needed for GiNaC::compile).
 GINAC_EXCOMPILER