Description

I open a project in Tcl mode and run synth_design. 

When it completes I type 'start_gui'. 

The GUI appears, but a warning is displayed in the yellow message bar at the top:

Synthesized Design out of date. Design sources were modified

If I click 'More Info' it says "File order changed"

Why does this occur?

解决方案

Even though from the user point of view they are only launching the GUI, there is more happening in the background. 

Initially, in the Tcl script there was nothing done to re-order the files automatically.

However, when the GUI is launched, it needs to show the hierarchical view of the sources.

To do so it calls update graph, which in automatic mode also reorders the files.

Before running "start_gui", if you manually run "reorder_files -auto," then you will NOT see the out of date message when the GUI is launched.

The key difference here is that running "open_project" then "synth_design" from Tcl is NOT equivalent to "opening a project in the GUI" (which also does re-ordering) and then running synthesis. 

The below commands should be equivalent:

open_project
launch_runs synth_1

The below commands are almost equivalent (though not exactly the same, because launch_runs synth_1 is not the same as synth_design).

open_project
reorder_files -auto
synth_design