Produce a useful error message instead of undefined (gh-96)

Criterion/Internal.hs

@@ -171,7 +171,8 @@ for select bs0 handle = go (0::Int) ("", bs0) >> return ()
       foldM go idx [(addPrefix pfx desc, b) | b <- bs]
 
     shouldRun pfx mkbench =
-      any (select . addPrefix pfx) . benchNames . mkbench $ undefined
+      any (select . addPrefix pfx) . benchNames . mkbench $
+      error "Criterion.env could not determine the list of your benchmarks since they force the environment (see the documentation for details)"
 
 -- | Write summary JUnit file (if applicable)
 junit :: [Report] -> Criterion ()

changelog.md

@@ -1,4 +1,18 @@
-* The "--only-run" option for benchmarks is renamed to "--iters".
+1.1.1.0
+
+*
+
+* We now flush stdout and stderr after printing messages, so that
+  output is printed promptly even when piped (e.g. into a pager).
+
+* A new function `runMode` allows custom benchmarking applications to
+  run benchmarks with control over the `Mode` used.
+
+* Added support for Linux on non-Intel CPUs.
+
+* This version supports GHC 8.
+
+* The `--only-run` option for benchmarks is renamed to `--iters`.
 
 1.1.0.0