Improved detection of build errors.

src/recipe.cr

@@ -275,7 +275,8 @@ class Package::Recipe
 
 		instructions.to_a.each do |instruction|
 			if instruction.run(@context, self).failed?
-				break BuildStatus::Failed
+				success = false
+				break
 			end
 		end
 
@@ -283,7 +284,7 @@ class Package::Recipe
 
 		ENV["PKG"] = nil
 
-		do_splits
+		do_splits if success
 
 		success
 	end