[Scons-users] SCons not actually not using timestamp-newer decider correctly.

[Lyuwen Fu]

Hi,

When I am trying to use timestamp-newer decider in scons. Scons is still trying to create a '.sconsign.dblite' file. And if the file does not exist. Scons will not compare the timestamp between the targets and dependencies to determine whether or not to rebuild. This is not the same as it is described "This is the behavior of the classic Make utility", because make does not generate any extra files.

To recreate this issue, just execute:
```
touch dep target
echo “env = Environment()” > SConstruct
echo “env.Decider("make”)” >> SConstruct
echo “env.Command('target', 'dep', 'touch target’)” >> SConstruct
scons -n
```
The output will show the "'touch target” command even if 'target' has a timestamp newer than 'dep’.


================================
Lyuwen Fu
Ph.D. Candidate
Columbia University
fulvwen at gmail.com
(347) 208-5539