diff --git a/setup.py b/setup.py
--- a/setup.py
+++ b/setup.py
@@ -773,14 +773,10 @@
             f.write(b'/* this file is autogenerated by setup.py */\n')
             f.write(b'#define HGPYTHONLIB "%s"\n' % pythonlib)
 
-        macros = None
-        if sys.version_info[0] >= 3:
-            macros = [('_UNICODE', None), ('UNICODE', None)]
-
         objects = self.compiler.compile(
             ['mercurial/exewrapper.c'],
             output_dir=self.build_temp,
-            macros=macros,
+            macros=[('_UNICODE', None), ('UNICODE', None)],
         )
         self.compiler.link_executable(
             objects, self.hgtarget, libraries=[], output_dir=self.build_temp