[PATCH cygport] Add initial support for SOURCE_DATE_EPOCH

[Christian Franke]

ASSI via Cygwin-apps wrote:
> Christian Franke via Cygwin-apps writes:
>> If the build-path changes, more files differ (cygcheck.exe, ldd.exe,
>> cygserver.exe) because __FILE__ is used and expands to an absolute
>> path name.
> This could be fixed by adding -fmacro-prefix and/or -ffile-prefix arguments.

Yes, -fmacro-prefix-map should do the trick.

Meantime I found a workaround for the additional timestamp in the PE 
Export Tables header:
The ld option --no-insert-timestamp also sets this timestamp to 0. This 
is apparently preserved by objcopy, regardless of --preserve-dates option.

-- 
Regards,
Christian