Cleanup: bison and flex detection

[babeltrace.git] / m4 / ax_prog_bison_version.m4

diff --git a/m4/ax_prog_bison_version.m4 b/m4/ax_prog_bison_version.m4
index 5da478c18b35d0541a1c192b8e6c032b223fde51..5a8888dea2cc73fcf7cf1c871e448b2d140302d0 100644 (file)
--- a/m4/ax_prog_bison_version.m4
+++ b/m4/ax_prog_bison_version.m4
@@ -1,5 +1,5 @@
 # ===========================================================================
-#   http://www.gnu.org/software/autoconf-archive/ax_prog_bison_version.html
+#   https://www.gnu.org/software/autoconf-archive/ax_prog_bison_version.html
 # ===========================================================================
 #
 # SYNOPSIS
@@ -11,41 +11,49 @@
 #   Makes sure that bison version is greater or equal to the version
 #   indicated. If true the shell commands in ACTION-IF-TRUE are executed. If
 #   not the shell commands in commands in ACTION-IF-TRUE are executed. If
-#   not the shell commands in ACTION-IF-FALSE are run. Note if $BISON is not
-#   set (for example by running AC_CHECK_PROG or AC_PATH_PROG) the macro
+#   not the shell commands in ACTION-IF-FALSE are run. Note if $YACC is not
+#   set (for example by running AC_PROG_YACC or AC_PATH_PROG) the macro
 #   will fail.
 #
 #   Example:
 #
-#     AC_PATH_PROG([BISON],[bison])
+#     AC_PROG_YACC
 #     AX_PROG_BISON_VERSION([3.0.2],[ ... ],[ ... ])
 #
 #   This will check to make sure that the bison you have is at least version
 #   3.0.2 or greater.
 #
-#   NOTE: This macro uses the $BISON variable to perform the check.
+#   NOTE: This macro uses the $YACC variable to perform the check, if it's
+#   empty it will failover to the $BISON variable for backwards compatibility.
 #
 # LICENSE
 #
 #   Copyright (c) 2015 Jonathan Rajotte-Julien <jonathan.rajotte-julien@efficios.com>
+#                 2017 Michael Jeanson <mjeanson@efficios.com>
 #
 #   Copying and distribution of this file, with or without modification, are
 #   permitted in any medium without royalty provided the copyright notice
 #   and this notice are preserved. This file is offered as-is, without any
 #   warranty.
 
-#serial 2
+#serial 4
 
 AC_DEFUN([AX_PROG_BISON_VERSION],[
     AC_REQUIRE([AC_PROG_SED])
     AC_REQUIRE([AC_PROG_GREP])
 
-    AS_IF([test -n "$BISON"],[
+     AS_IF([test -z "$YACC"],[
+         AS_IF([test -n "$BISON"],[
+             YACC=$BISON
+         ])
+     ])
+
+    AS_IF([test -n "$YACC"],[
         ax_bison_version="$1"
 
         AC_MSG_CHECKING([for bison version])
         changequote(<<,>>)
-        bison_version=`$BISON --version 2>&1 \
+        bison_version=`$YACC --version 2>&1 \
           | $SED -n -e '/bison (GNU Bison)/b inspect
 b
 : inspect