diff --git a/make/autoconf/basic.m4 b/make/autoconf/basic.m4
index 0e9470a1cff..2d3e071dd52 100644
--- a/make/autoconf/basic.m4
+++ b/make/autoconf/basic.m4
@@ -415,11 +415,21 @@ AC_DEFUN_ONCE([BASIC_SETUP_OUTPUT_DIR],
       [ CONF_NAME=${with_conf_name} ])
 
   # Test from where we are running configure, in or outside of src root.
+  if test "x$OPENJDK_BUILD_OS" = xwindows || test "x$OPENJDK_BUILD_OS" = "xmacosx"; then
+    # These systems have case insensitive paths, so convert them to lower case.
+    [ cmp_configure_start_dir=`$ECHO $CONFIGURE_START_DIR | $TR '[:upper:]' '[:lower:]'` ]
+    [ cmp_topdir=`$ECHO $TOPDIR | $TR '[:upper:]' '[:lower:]'` ]
+    [ cmp_custom_root=`$ECHO $CUSTOM_ROOT | $TR '[:upper:]' '[:lower:]'` ]
+  else
+    cmp_configure_start_dir="$CONFIGURE_START_DIR"
+    cmp_topdir="$TOPDIR"
+    cmp_custom_root="$CUSTOM_ROOT"
+  fi
   AC_MSG_CHECKING([where to store configuration])
-  if test "x$CONFIGURE_START_DIR" = "x$TOPDIR" \
-      || test "x$CONFIGURE_START_DIR" = "x$CUSTOM_ROOT" \
-      || test "x$CONFIGURE_START_DIR" = "x$TOPDIR/make/autoconf" \
-      || test "x$CONFIGURE_START_DIR" = "x$TOPDIR/make" ; then
+  if test "x$cmp_configure_start_dir" = "x$cmp_topdir" \
+      || test "x$cmp_configure_start_dir" = "x$cmp_custom_root" \
+      || test "x$cmp_configure_start_dir" = "x$cmp_topdir/make/autoconf" \
+      || test "x$cmp_configure_start_dir" = "x$cmp_topdir/make" ; then
     # We are running configure from the src root.
     # Create a default ./build/target-variant-debuglevel output root.
     if test "x${CONF_NAME}" = x; then
@@ -440,7 +450,12 @@ AC_DEFUN_ONCE([BASIC_SETUP_OUTPUT_DIR],
     # If configuration is situated in normal build directory, just use the build
     # directory name as configuration name, otherwise use the complete path.
     if test "x${CONF_NAME}" = x; then
-      CONF_NAME=`$ECHO $CONFIGURE_START_DIR | $SED -e "s!^${TOPDIR}/build/!!"`
+      [ if [[ "$cmp_configure_start_dir" =~ ^${cmp_topdir}/build/[^/]+$ ||
+          "$cmp_configure_start_dir" =~ ^${cmp_custom_root}/build/[^/]+$ ]]; then ]
+          CONF_NAME="${CONFIGURE_START_DIR##*/}"
+      else
+          CONF_NAME="$CONFIGURE_START_DIR"
+      fi
     fi
     OUTPUTDIR="$CONFIGURE_START_DIR"
     AC_MSG_RESULT([in current directory])