seems windows sh doesn't properly handle set -e in functions

standalone/windows/build.sh

@@ -35,8 +35,10 @@ cd ..
 
 cabal install --only-dependencies -f"$FLAGS"
 
-runbuild () {
-	set -e
+if ! -e last-incremental-failed; then
+	cabal clean
+fi
+touch last-incremental-failed
 
 # Build git-annex
 withcyg cabal configure -f"$FLAGS"
@@ -46,15 +48,8 @@ runbuild () {
 cabal install nsis
 ghc --make Build/NullSoftInstaller.hs
 withcyg Build/NullSoftInstaller.exe
-}
 
-# Incremental build sometimes may fail, possibly because the configure
-# script has changed but cabal neglects to re-build it on Windows
-if ! runbuild; then
-	echo "Retrying after cabal clean"
-	cabal clean
-	runbuild
-fi
+rm -f last-incremental-failed
 
 # Test git-annex
 rm -rf .t