speed up fast builds

Enabling -dynamic avoids writing out many mb of static libs.

-j parallelizes

Makefile

@@ -200,7 +200,7 @@ ANDROID_FLAGS?=
 # Uses https://github.com/neurocyte/ghc-android
 android: Build/EvilSplicer
 	echo "Running native build, to get TH splices.."
-	if [ ! -e dist/setup/setup ]; then $(CABAL) configure -f-Production -O0 $(ANDROID_FLAGS) -fAndroidSplice;  fi
+	if [ ! -e dist/setup/setup ]; then $(CABAL) configure -O0 $(ANDROID_FLAGS) -fAndroidSplice;  fi
 	mkdir -p tmp
 	if ! $(CABAL) build --ghc-options=-ddump-splices 2> tmp/dump-splices; then tail tmp/dump-splices >&2; exit 1; fi
 	echo "Setting up Android build tree.."
@@ -240,7 +240,7 @@ androidapp:
 # fast development built. Note: Does not rebuild C libraries, or link
 # executable.
 fast: dist/caballog
-	@$$(grep 'ghc --make' dist/caballog | head -n 1 | sed -e 's/-package-id [^ ]*//g' -e 's/-hide-all-packages//') -O0
+	@$$(grep 'ghc --make' dist/caballog | head -n 1 | sed -e 's/-package-id [^ ]*//g' -e 's/-hide-all-packages//') -O0 -j -dynamic
 	@ln -sf dist/build/git-annex/git-annex git-annex
 	@$(MAKE) tags >/dev/null 2>&1 &
 

git-annex.cabal

@@ -153,8 +153,6 @@ Executable git-annex
     Build-Depends: cryptohash (>= 0.11.0)
 
   -- Fully optimize for production.
-  -- Parallel builds only when not building for production,
-  -- because ghc is known to not yield reproducible builds this way.
   if flag(Production)
     GHC-Options: -O2