From fa76d8646bb2b9b514728eeef41afed7c43a36f2 Mon Sep 17 00:00:00 2001
From: Khem Raj <raj.khem@gmail.com>
Date: Tue, 11 Sep 2018 18:18:33 -0700
Subject: [PATCH] Check for clang before using -isystem

When cross compiling with clang, the internal C++ headers are not found
when adding sysroot to -isystem, that is redundant anyway because it
will look for headers insider --sysroot path with same quality as it
would do with -isystem otherwise

Upstream-Status: Submitted [https://github.com/opencv/opencv/pull/12504]
Signed-off-by: Khem Raj <raj.khem@gmail.com>
---
 cmake/OpenCVUtils.cmake | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cmake/OpenCVUtils.cmake b/cmake/OpenCVUtils.cmake
index fae91c165f..60c20192dc 100644
--- a/cmake/OpenCVUtils.cmake
+++ b/cmake/OpenCVUtils.cmake
@@ -259,7 +259,7 @@ function(ocv_include_directories)
     ocv_is_opencv_directory(__is_opencv_dir "${dir}")
     if(__is_opencv_dir)
       list(APPEND __add_before "${dir}")
-    elseif(CV_GCC AND NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS "6.0" AND
+    elseif(((CV_GCC AND NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS "6.0") OR CV_CLANG) AND
            dir MATCHES "/usr/include$")
       # workaround for GCC 6.x bug
     else()
-- 
2.18.0