--- a/avilib/Makefile.am
+++ b/avilib/Makefile.am
@@ -7,7 +7,8 @@
 
 INCLUDES = -I./
 
-CFLAGS=-O3 -funroll-loops -ffast-math -DLINUX -Wall @CFLAGS@
+AM_CFLAGS=-Wall
+AM_CPPFLAGS=-DLINUX
 libavi_a_SOURCES = avilib.c avidump.c avimisc.c xio.c
 
 EXTRA_DIST = avilib.h README.avilib
--- a/configure.in
+++ b/configure.in
@@ -8,6 +8,7 @@
 AC_PROG_GCC_TRADITIONAL
 AC_PROG_CPP
 AC_PROG_RANLIB
+AM_PROG_AR
 
 XIPH_PATH_OGG()
 XIPH_PATH_VORBIS()
@@ -31,7 +32,7 @@
 dnl Check for headers
 AC_HEADER_STDC()
 
-CFLAGS="-Wall -Wno-sign-compare @OGG_CFLAGS@ @VORBIS_CFLAGS@ @AVILIB_CFLAGS@ @DEBUG_CFLAGS@ @PROFILING_CFLAGS@"
-CXXFLAGS="-Wall -Wno-sign-compare @OGG_CFLAGS@ @VORBIS_CFLAGS@ @AVILIB_CFLAGS@ @DEBUG_CFLAGS@ @PROFILING_CFLAGS@"
+CFLAGS+=" -Wall -Wno-sign-compare"
+CXXFLAGS+=" -Wall -Wno-sign-compare"
 
 AC_OUTPUT(Makefile avilib/Makefile)
--- a/Makefile.am
+++ b/Makefile.am
@@ -2,6 +2,9 @@
 
 AUTOMAKE_OPTIONS = dist-zip foreign
 
+AM_CFLAGS=$(OGG_CFLAGS) $(VORBIS_CFLAGS) $(AVILIB_CFLAGS) $(DEBUG_CFLAGS) $(PROFILING_CFLAGS)
+AM_CXXFLAGS=$(OGG_CFLAGS) $(VORBIS_CFLAGS) $(AVILIB_CFLAGS) $(DEBUG_CFLAGS) $(PROFILING_CFLAGS)
+
 SUBDIRS = avilib
 
 if HAVE_LIBDVDREAD