--- flang/tools/f18/flang.sh.in.orig
+++ flang/tools/f18/flang.sh.in
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/bin/sh
 #===-- tools/f18/flang.sh -----------------------------------------*- sh -*-===#
 #
 # Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
@@ -7,23 +7,6 @@
 #
 #===------------------------------------------------------------------------===#
 
-function abspath() {
-  pushd . > /dev/null;
-  if [ -d "$1" ]; then
-    cd "$1";
-    dirs -l +0;
-  else
-    cd "`dirname \"$1\"`";
-    cur_dir=`dirs -l +0`;
-    if [ "$cur_dir" == "/" ]; then
-      echo "$cur_dir`basename \"$1\"`";
-    else
-      echo "$cur_dir/`basename \"$1\"`";
-    fi;
-  fi;
-  popd > /dev/null;
-}
-
-wd=`abspath $(dirname "$0")/..`
+wd=`realpath $(dirname "$0")/..`
 
 ${wd}/bin/f18 -module-suffix .f18.mod -intrinsic-module-directory @FLANG_INTRINSIC_MODULES_DIR@ $*