[Scons-users] scons 3.0.1: 'ascii' codec can't decode

[mpac1234 at will-hier-weg.de]

Hello,
 
when trying to move from scons 2.5.1 to scons 3.0.1 on Windows with Python 2.7.13 the following stopped working for me (does not work with python 3.6.3 either), with main.cpp being a hello world program:
--------------------------
import os
env = Environment(tools = ["mingw"], ENV=os.environ)
prog = env.Program("main", ["main.cpp"])
run = env.Command(Value("testrun"), prog, "$SOURCE")
env.Alias("run", run)
AlwaysBuild(run)
--------------------------
 
With scons 2.5.1 this works, with scons 3.0.1 it does not:
scons: *** [testrun] UnicodeDecodeError : 'ascii' codec can't decode byte 0x90 in position 2: ordinal not in range(128)
This one works
--------------------------
import os
env = Environment(tools = ["mingw"], ENV=os.environ)
prog = env.Program("main", ["main.cpp"])
run = env.Alias("run", prog, prog[0].abspath)
AlwaysBuild(run)
--------------------------
But I wondered if the first *should* work.