Build benchmarks in .stack-work-bench

Author: phadej

.gitignore

@@ -4,6 +4,7 @@ dist-newstyle
 .cabal-sandbox/
 cabal.sandbox.config
 .stack-work/
+.stack-work-bench/
 
 *.o
 *.hi

stack-bench.yaml

@@ -1,10 +1,13 @@
 resolver: lts-8.5
-packages:
 # We use aeson in the snapshot to
 # - avoid recompilation of criterion
 # - compare against it
-
 # - '.'
+#
+# Also we use separate working directory to avoid "unregistering aeson"
+# caused recompilations
+work-dir: .stack-work-bench
+packages:
 - benchmarks
 extra-deps:
 - aeson-1.2.1.0