From 73b0297e5e30e3cf78ea4d2fd553e3bde0f2d4bb Mon Sep 17 00:00:00 2001
From: "James R. Barlow" <jim@purplerock.ca>
Date: Wed, 26 Aug 2015 02:17:10 -0700
Subject: [PATCH] Fix configure.ac unconditionally enabling OpenCL

---
 configure.ac | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/configure.ac b/configure.ac
index c6fd06d15b..1ed3db0621 100644
--- a/configure.ac
+++ b/configure.ac
@@ -221,9 +221,14 @@ case "${host_os}" in
     if test $my_cv_framework_OpenCL = yes; then
        have_opencl_lib=true
     fi
-    AC_SUBST([AM_CPPFLAGS], [-DUSE_OPENCL])
-    OPENCL_CPPFLAGS=""
-    OPENCL_LDFLAGS="-framework OpenCL"
+    if test "$enable_opencl" = "yes"; then
+      if !($have_opencl_lib); then
+        AC_MSG_ERROR(Required OpenCL library not found!)
+      fi
+      AC_SUBST([AM_CPPFLAGS], [-DUSE_OPENCL])
+      OPENCL_CPPFLAGS=""
+      OPENCL_LDFLAGS="-framework OpenCL"
+    fi
     ;;
   *)
     # default