{ stdenv, fetchurl, bison, m4 }: stdenv.mkDerivation { name = "flex-2.5.39"; src = fetchurl { url = mirror://sourceforge/flex/flex-2.5.39.tar.bz2; sha256 = "0zv15giw3gma03y2bzw78hjfy49vyir7vbcgnh9bb3637dgvblmd"; }; buildInputs = [ bison ]; propagatedNativeBuildInputs = [ m4 ]; postConfigure = stdenv.lib.optionalString (stdenv.isDarwin || stdenv.isCygwin) '' sed -i Makefile -e 's/-no-undefined//;' ''; crossAttrs = { preConfigure = '' export ac_cv_func_malloc_0_nonnull=yes export ac_cv_func_realloc_0_nonnull=yes ''; }; meta = { homepage = http://flex.sourceforge.net/; description = "A fast lexical analyser generator"; }; }