[Rd] Inno Setup 6.0.2 fails before creating exe file on Windows (R-3.6.0)

[Avraham Adler]

I am working on compiling R-3.6.0 for Windows 10 64bit using rtools40
(beta 11). I had also installed the most recent update of Inno setup,
which is now 6.0.2.With that version, `make risntaller` fails at the
call to ""C:/R/Inno/iscc" R.iss > R-3.6.0.log 2>&1" and just exits,
pointing to line 175 of the makefile which is:

$(RPREFIX)-win.exe: R.iss
    "$(ISDIR)/iscc" R.iss > $(RPREFIX).log 2>&1

Reinstalling Inno Setup 5.6.1 does allow the exe file to be created.

Thank you,

Avi