From 937747323dd88e63e48a276391d2664cb0ecba67 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Atgeirr=20Fl=C3=B8=20Rasmussen?= <atgeirr@sintef.no>
Date: Fri, 29 May 2020 14:31:37 +0200
Subject: [PATCH] Ensure clang uses the normal standard headers.

Clang defines __GNUC__ to 4, as that represents its level of
support for the GNU C dialect. The gcc compiler does not provide
a macro indicating the compiler separately from the dialect supported.
We must therefore use the __clang__ macro to avoid false positives.
---
 opm/common/utility/FileSystem.hpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/opm/common/utility/FileSystem.hpp b/opm/common/utility/FileSystem.hpp
index 861c7db50..e3f0fe344 100644
--- a/opm/common/utility/FileSystem.hpp
+++ b/opm/common/utility/FileSystem.hpp
@@ -20,7 +20,7 @@
 #define OPM_FILESYSTEM_HPP
 
 #if __cplusplus < 201703L || \
-    (defined(__GNUC__) && __GNUC__ < 8)
+    (defined(__GNUC__) && __GNUC__ < 8 && !defined(__clang__))
 #include <experimental/filesystem>
 #else
 #include <filesystem>
@@ -32,7 +32,7 @@
 namespace Opm
 {
 #if __cplusplus < 201703L || \
-    (defined(__GNUC__) && __GNUC__ < 8)
+    (defined(__GNUC__) && __GNUC__ < 8 && !defined(__clang__))
     namespace filesystem = std::experimental::filesystem;
 #else
     namespace filesystem = std::filesystem;