--- src/xxdiff.pro.orig	2019-06-27 08:14:43.000000000 -0700
+++ src/xxdiff.pro	2019-06-27 08:48:54.000000000 -0700
@@ -145,29 +145,13 @@
    dmg.commands = @hdiutil create -ov -fs HFS+ -srcfolder $$BUNDLE -volname $$quote("xxdiff\\ $$VER") $$DMG
    dmg.depends = $$macdeployqt.target $(TARGET)
 
-   # Crappy crap to generate and use a specific bison source file that is compatible with bison 2.3 (the default on OSX)
-   bison23lnk.target = resParser_yacc.h
-   bison23lnk.commands = rm -f resParser_yacc.h resParser_yacc.cpp; ln -s resParser_bison23_yacc.cpp resParser_yacc.cpp; ln -s resParser_bison23_yacc.h resParser_yacc.h
-   bison23lnk.depends = bison23src resParser_bison23_yacc.h resParser_bison23.y
-   bison23src.target = resParser_bison23.y
-   bison23src.commands = perl -pe \'s/define api.pure/pure-parser/\' resParser.y > resParser_bison23.y
-   bison23src.depends = 
-   YACCSOURCES = resParser_bison23.y
-   QMAKE_YACCFLAGS_MANGLE = -p resParser -b resParser
-   resParser_lex_obj.target = resParser_lex.o
-   resParser_lex_obj.depends = bison23lnk
-
    # "register" deprecated in C++11 but the MacOS flex still uses it in files it generates
    QMAKE_LEXFLAGS += -Dregister=
 
    # "public" rule
    deploy.depends = $$dmg.target
 
-   QMAKE_EXTRA_TARGETS += macdeployqt dmg deploy bison23src bison23lnk resParser_lex_obj
-   QMAKE_CFLAGS_RELEASE   -= -O2
-   QMAKE_CXXFLAGS_RELEASE -= -O2
-   QMAKE_CFLAGS   += -mdynamic-no-pic -O3 -msse2 -msse3 -mssse3 -ftree-vectorize
-   QMAKE_CXXFLAGS += -mdynamic-no-pic -O3 -msse2 -msse3 -mssse3 -ftree-vectorize
+   QMAKE_EXTRA_TARGETS += macdeployqt dmg deploy
 }
 
 #----------------------------------------