diff --git a/SCons/Config/gnu b/SCons/Config/gnu
index de1a93e3..2b276be9 100644
--- a/SCons/Config/gnu
+++ b/SCons/Config/gnu
@@ -35,7 +35,7 @@ defenv['STDCALL'] = '__attribute__((__stdcall__))'
 
 ### defines
 
-defenv.Append(CPPDEFINES = {'NSISCALL' : '$STDCALL'})
+defenv.Append(CPPDEFINES = {'NSISCALL' : ' $STDCALL'})
 
 ### helper functions