[appveyor] save and cache

appveyor.yml

@@ -27,6 +27,8 @@ cache:
   - '%USERPROFILE%\clcache'
 
 environment:
+  global:
+    APPVEYOR_SAVE_CACHE_ON_ERROR: true
   matrix:
     - COMPILER: clang-cl
       DYNAMIC_ARCH: ON
@@ -44,6 +46,8 @@ before_build:
   - echo Running cmake...
   - cd c:\projects\OpenBLAS
   - set CLCACHE_CL=%COMPILER%
+  - clcache -M 644245094
+  - clcache -c
   - if [%COMPILER%]==[cl] cmake -G "Visual Studio 12 Win64" -DCMAKE_CXX_COMPILER=clcache -DCMAKE_C_COMPILER=clcache .
   - if [%COMPILER%]==[clang-cl] cmake -G "Ninja" -DCMAKE_CXX_COMPILER=clcache -DCMAKE_C_COMPILER=clcache .
   - if [%DYNAMIC_ARCH%]==[ON] cmake -DDYNAMIC_ARCH=ON .