Try to get build to work in appveyor

appveyor.yml

@@ -1,18 +1,41 @@
+platform:
+  - x86
+  - x64
 os: MinGW
 environment:
   matrix:
-  - TARGET: i686-pc-windows-gnu
-    OPENSSL_INCLUDE_DIR: C:\OpenSSL-Win32\include
-    OPENSSL_LIB_DIR: C:\OpenSSL-Win32\lib
-    OPENSSL_LIBS: ssleay32:libeay32
+  - RUST_VERSION: 1.5.0
+cache:
+  - '%HOME%\.cargo'
 install:
-  - ps: Start-FileDownload "http://win32builder.gnome.org/gtk+-bundle_3.10.4-20131202_win32.zip" -FileName gtk.zip
+  - if "%PLATFORM%" == "x86" SET RUST_PLATFORM=i686-pc-windows-gnu
+  - if "%PLATFORM%" == "x64" SET RUST_PLATFORM=x86_64-pc-windows-gnu
+  - if "%PLATFORM%" == "x86" SET OPENSSL_INCLUDE_DIR: C:\OpenSSL-Win32\include
+  - if "%PLATFORM%" == "x86" SET OPENSSL_LIB_DIR: C:\OpenSSL-Win32\lib
+  - if "%PLATFORM%" == "x64" SET OPENSSL_INCLUDE_DIR: C:\OpenSSL-Win64\include
+  - if "%PLATFORM%" == "x64" SET OPENSSL_LIB_DIR: C:\OpenSSL-Win64\lib
+  - SET OPENSSL_LIBS: ssleay32:libeay32
+  - ps: >-
+      if ($Env:PLATFORM -eq "x86") {
+        Start-FileDownload "http://win32builder.gnome.org/gtk+-bundle_3.10.4-20131202_win32.zip" -FileName gtk.zip
+        Start-FileDownload "http://libgd.blob.core.windows.net/mingw/i686-4.9.1-release-posix-dwarf-rt_v3-rev1.7z" -FileName mingw.7z;
+        $Env:MINGW = "C:\mingw32"
+      }
+      else {
+        Start-FileDownload "http://win32builder.gnome.org/gtk+-bundle_3.10.4-20131202_win64.zip" -FileName gtk.zip
+        Start-FileDownload "http://libgd.blob.core.windows.net/mingw/mingw-w64-dgn-x86_64-20141001.7z" -FileName mingw.7z;
+        $Env:MINGW = "C:\mingw64"
+      }
+  - ps: 7z x -oC:\ mingw.7z | Out-Null;
   - ps: 7z x -oC:\Gtk gtk.zip | Out-Null
-  - ps: Start-FileDownload "https://static.rust-lang.org/dist/rust-nightly-${env:TARGET}.exe"
-  - rust-nightly-%TARGET%.exe /VERYSILENT /NORESTART /DIR="C:\Program Files (x86)\Rust"
-  - SET PATH=%PATH%;C:\Program Files (x86)\Rust\bin
-  - SET PATH=%PATH%;C:\MinGW\bin
+  - ps: Start-FileDownload "https://static.rust-lang.org/dist/rust-${env:RUST_VERSION}-${env:RUST_PLATFORM}.exe" -FileName rust-installer.exe
+  - rust-installer.exe /VERYSILENT /NORESTART /DIR="C:\Rust"
+  - SET PATH=%PATH%;C:\Rust\bin
   - SET PATH=C:\Gtk\bin;%PATH%
+  - SET PATH=%PATH%;%MINGW%\bin
+  - echo %PATH%
+  - pkg-config --libs --cflags gtk+-3.0 # check if pkg-config works
+  - gcc --version
   - rustc -V
   - cargo -V