Repeatable builds with Visual C++ ?

[Johan Holmberg]

Hi Cons-users !

I wonder if anyone knows if it is possible to reproduce an exe-file
"byte-by-byte" with Visual C++.

Visual C++ puts timestamps in the object files, but I think I found
a way around that by running "dumpbin" on the resulting exe, like
this:

       1) remove all object- and exe-files
       2) compile/link appl. with Cons.
       3) run "dumpbin /all EXEFILE > EXEFILE.dump-1
       4) remove all object- and exe-files
       5) compile/link appl. with Cons.
       6) run "dumpbin /all EXEFILE > EXEFILE.dump-2
       7) run "diff EXEFILE.dump-1 EXEFILE.dump-2"


I tried this first on a rather small application, and seemed to get
the same content at both times (only the timestamps differed).

But when I tested it on a little bigger application (about 700 C++
files) I seem to get quite many differences (apart from the
timestamps).

Does anyone know anything about this problem ?

I don't like having a very good make tool (Cons) to be able to build
things accurately, and then have acompiler that (maybe) produces
different code on each invocation.

I know no way of actually verifying that the differences are
harmless. What besides timestamps may differ without being "harmful" ?

/Johan Holmberg