Fix build with gcc-7 on linux (WIP)

Not very clean, needs improvement

CMakeLists.txt

@@ -8,6 +8,8 @@ if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND NOT ANDROID)
     add_compile_options(-stdlib=libc++)
     # Presumably need the above for linking too, maybe other options missing as well
     add_link_options(-stdlib=libc++)   # New command on CMake master, not in 3.12 release
+else()
+    add_link_options(-lstdc++fs)
 endif()
 
 if (UNIX) 

clients/sfzprint.cpp

@@ -23,8 +23,8 @@
 
 #include "Parser.h"
 #include "StringViewHelpers.h"
+#include "filesystem.h"
 #include <iostream>
-#include <filesystem>
 #include <string_view>
 #include <absl/flags/parse.h>
 #include <absl/types/span.h>
@@ -92,4 +92,4 @@ int main(int argc, char** argv)
         std::cout << '\t' << define.first << '=' << define.second << '\n';
     // spdlog::info("Done!");
     return 0;
-}
+}

sfizz/FilePool.h

@@ -27,9 +27,9 @@
 #include "LeakDetector.h"
 #include "AudioBuffer.h"
 #include "Voice.h"
+#include "filesystem.h"
 #include "readerwriterqueue.h"
 #include <absl/container/flat_hash_map.h>
-#include <filesystem>
 #include <optional>
 #include <string_view>
 #include <thread>
@@ -75,4 +75,4 @@ private:
     absl::flat_hash_map<std::string_view, std::shared_ptr<AudioBuffer<float>>> preloadedData;
     LEAK_DETECTOR(FilePool);
 };
-}
+}

sfizz/Parser.h

@@ -23,7 +23,7 @@
 
 #pragma once
 #include "Opcode.h"
-#include <filesystem>
+#include "filesystem.h"
 #include <map>
 #include <regex>
 #include <string>
@@ -59,4 +59,4 @@ private:
     void readSfzFile(const std::filesystem::path& fileName, std::vector<std::string>& lines) noexcept;
 };
 
-} // namespace sfz
+} // namespace sfz

sfizz/filesystem.h

@@ -0,0 +1,33 @@
+// Copyright (c) 2019, Paul Ferrand
+// All rights reserved.
+
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#pragma once
+
+#ifdef __linux__
+#include <experimental/filesystem>
+namespace std {
+    namespace filesystem = std::experimental::filesystem;
+}
+#else
+#include <filesystem>
+#endif