configure: Define DEFAULT_M4 by searching PATH.

        * configure: Define DEFAULT_M4 by searching PATH.
        * Makfile.in: Use DEFAULT_M4.

From-SVN: r19208

1 files changed, 20 insertions, 0 deletions

diff --git a/configure b/configure
index ed54cedbde3..8b4e510d0bf 100755
--- a/configure
+++ b/configure
@@ -762,6 +762,25 @@ do
   test -n "$DEFAULT_YACC" && break
 done
 
+# Generate a default definition for M4.  This is used if the makefile can't
+# locate m4 in objdir.
+
+for prog in gm4 gnum4 m4
+do
+  set dummy $prog; tmp=$2
+  IFS="${IFS=   }"; save_ifs="$IFS"; IFS="${IFS}:"
+  for dir in $PATH; do
+    test -z "$dir" && dir=.
+    if test -f $dir/$tmp; then
+      DEFAULT_M4="$prog"
+      break
+    fi
+  done
+  IFS="$save_ifs"
+
+  test -n "$DEFAULT_M4" && break
+done
+
 # Generate a default definition for LEX.  This is used if the makefile can't
 # locate flex in objdir.
 
@@ -1259,6 +1278,7 @@ EOF
                     -e "s|^tooldir[ 	]*=.*$|tooldir = ${tooldir}|" \
 		    -e "s:^DEFAULT_YACC[	 ]*=.*$:DEFAULT_YACC = ${DEFAULT_YACC}:" \
 		    -e "s:^DEFAULT_LEX[	 ]*=.*$:DEFAULT_LEX = ${DEFAULT_LEX}:" \
+		    -e "s:^DEFAULT_M4[  ]*=.*$:DEFAULT_M4 = ${DEFAULT_M4}:" \
                     ${subdir}/Makefile.tem >> ${Makefile}
 
 	    # If this is a Canadian Cross, preset the values of many more