I've tried the new tree and generating a new gnuplot.exe was successful.
Now my attention focused on why generating the help is not optimal.
With "NO_GIH", a help library should be generated. VMS's RUNOFF does not like the following line (for "help labels"):
3665 symbol(z) = "âˆ™â–¡+âŠ™â™ â™£â™¡â™¢"[int(z):int(z)]
While RUNOFF gives just a warning, the build procedure stops. Would there be another way of documenting this line?
And without "NO_GIH" the "gnuplot.gih" is not generated automatically, so I'm planning to patch "configure.vms" a final time.