Work on CI support for MingW

.appveyor.yml

@@ -1,5 +1,29 @@
 environment:
   matrix:
+    - platform: x86
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
+      generator: "Visual Studio 14 2015"
+      compiler: msvc
+      configuration: Release
+
+    - platform: x64
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
+      generator: "Visual Studio 14 2015 Win64"
+      compiler: msvc
+      configuration: Release
+
+    - platform: x86
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
+      generator: "Visual Studio 15 2017"
+      compiler: msvc
+      configuration: Release
+
+    - platform: x64
+      APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017
+      generator: "Visual Studio 15 2017 Win64"
+      compiler: msvc
+      configuration: Release
+
     - platform: x86
       APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
       generator: "MinGW Makefiles"

README.md

@@ -61,8 +61,8 @@ of the UTF-8 preference on Windows).
 
 Unit tests are currently run with:
 
-* macOS 10.12: XCode 9.2 (clang-900.0.39.2), GCC 8.1.0, Clang 7.0.0
+* macOS 10.12: Xcode 9.2 (clang-900.0.39.2), Xcode 10.2, GCC 8.1.0, Clang 7.0.0
-* Windows 10: Visual Studio 2017 15.8.5, MingW GCC 5.3
+* Windows: Visual Studio 2017, Visual Studio 2015, MingW GCC 6.3 (Win32), GCC 7.2 (Win64)
 * Linux (Ubuntu): GCC (5.5, 6.5, 7.4, 8.1, 8.2), Clang (5.0, 6.0, 7.1, 8.0)
 
 
@@ -445,6 +445,11 @@ to the expected behavior.
 
 ## Release Notes
 
+### v1.1.5 (wip)
+
+* Added MingW 32/64 and Visual Studio 2015 builds to the CI configuration.
+* Fixed additional compilation issues on MingW.
+
 ### [v1.1.4](https://github.com/gulrak/filesystem/releases/tag/v1.1.4)
 
 * Additional Bugfix for ([#12](https://github.com/gulrak/filesystem/issues/12)),