diff --git a/configure b/configure
index 5cdff8855d..fa09962c77 100755
--- a/configure
+++ b/configure
@@ -1430,7 +1430,7 @@ if netbsd || dragonfly ; then
 fi
 
 if darwin; then
-  CFLAGS="$CFLAGS -mdynamic-no-pic -falign-loops=16 -shared-libgcc"
+  extra_cflags="-mdynamic-no-pic -falign-loops=16 -shared-libgcc $extra_cflags"
   _timer=timer-darwin.c
 fi
 
@@ -1465,7 +1465,7 @@ if amigaos ; then
   _sighandler=no
   _stream_cache=no
   def_stream_cache="#undef CONFIG_STREAM_CACHE"
-  CFLAGS="$CFLAGS -DNEWLIB -D__USE_INLINE__"
+  extra_cflags="-DNEWLIB -D__USE_INLINE__ $extra_cflags"
 fi
 
 if qnx ; then