diff --git a/configure.in b/configure.in
index fe393ce..b7f643c 100644
--- a/configure.in
+++ b/configure.in
@@ -156,13 +156,13 @@
 AC_SUBST(FLaC__USIZE64)
 
 SAVE_CFLAGS="$CFLAGS"
-CFLAGS='-I$(top_builddir) -I$(srcdir)/include -I $(top_srcdir)/include -Wall -W'
+CFLAGS='-I$(top_builddir) -I$(srcdir)/include -I $(top_srcdir)/include -I$(top_builddir)/include/FLAC'
 if test x$debug = xtrue; then
 	CFLAGS="$CFLAGS -g -O0 -DDEBUG"
 else
 	CFLAGS="$CFLAGS -O3 -DNDEBUG"
 	if test x$GCC = xyes; then
-		CFLAGS="$CFLAGS -fomit-frame-pointer -funroll-loops -finline-functions -Winline -DFLaC__INLINE=__inline__"
+		CFLAGS="$CFLAGS -fomit-frame-pointer -funroll-loops -finline-functions -Wall -W -Winline -DFLaC__INLINE=__inline__"
 	fi
 fi
 CFLAGS="$CFLAGS $SAVE_CFLAGS"