diff --git a/Makefile.am b/Makefile.am
index cf73e11..c93ec7c 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -7,8 +7,7 @@ libdice_la_SOURCES =	lib/dice_lexer.l \
 			lib/dice_parse.y \
 			lib/dice.h \
 			lib/dice.c \
-			lib/diceexpr.c \
-			lex.dp.c
+			lib/diceexpr.c
 
 include_HEADERS =	lib/dice.h
 
diff --git a/lib/dice_lexer.c b/lib/dice_lexer.c
deleted file mode 100644
index 0a53ca5..0000000
--- a/lib/dice_lexer.c
+++ /dev/null
@@ -1,2 +0,0 @@
-/* empty file, so that autotools has something to compile
- */
diff --git a/lib/dice_lexer.l b/lib/dice_lexer.l
index 981030c..f88efd7 100644
--- a/lib/dice_lexer.l
+++ b/lib/dice_lexer.l
@@ -1,6 +1,6 @@
-%option prefix="dp"
 %option bison-bridge
 %option reentrant
+%option outfile="../lib/dice_lexer.c"
 
 %{
 #define YYSTYPE DPSTYPE