Autoconf test for incompatible version of flex

[Greg Stark <gsstark(at)mit(dot)edu>]

This patch adds an autoconf test to check for the new incompatible version of
flex.


--- programs.m4.~1.12.~	2003-05-06 19:33:52.000000000 -0400
+++ programs.m4	2003-07-04 20:45:47.000000000 -0400
@@ -30,6 +30,10 @@
             pgac_broken_flex=$pgac_candidate
             continue
           fi
+          if $pgac_candidate --version | grep ' 2\.5\.[[3-9][0-9]]$' >/dev/null 2>&1; then
+            pgac_new_flex=$pgac_candidate
+            continue
+          fi
 
           pgac_cv_path_flex=$pgac_candidate
           break 2
@@ -49,6 +53,12 @@
 *** The Flex version 2.5.3 you have at $pgac_broken_flex contains a bug. You
 *** should get version 2.5.4 or later.])
   fi
+  if test -n "$pgac_new_flex"; then
+    AC_MSG_WARN([
+*** The Flex version you have at $pgac_new_flex is a version PostgreSQL does
+*** not support. There were major incompatible API changes in this release of
+*** Flex. To compile PostgreSQL you should get version no later than 2.5.4a.])
+  fi
 
   AC_MSG_WARN([
 *** Without Flex you will not be able to build PostgreSQL from CVS or



-- 
greg