build results change after 2038

[bmwiedemann]

While working on reproducible builds for openSUSE, I found that
our boost_1_81_0 package produced slightly different binaries when built on x86_64 after 2038 (compared to now or 2037 which are fully reproducible)

This can indicate that somewhere in the complex build logic, a 32-bit signed integer UNIX timestamp is used and overflowing after 2038-01-18

--- old /usr/lib64/libboost_log.so.1.81.0 (objdump)
+++ new /usr/lib64/libboost_log.so.1.81.0 (objdump)
@@ -6824,9 +6824,9 @@
  1acf8 77726170 70657249 4e53315f 31367265  wrapperINS1_16re
  1ad08 736f6c76 65725f73 65727669 6365494e  solver_serviceIN
  1ad18 53305f32 69703375 64704545 45454500  S0_2ip3udpEEEEE.
- 1ad28 6c696262 6f6f7374 5f746872 6561642e  libboost_thread.
- 1ad38 736f2e31 2e38312e 30006c69 62626f6f  so.1.81.0.libboo
- 1ad48 73745f66 696c6573 79737465 6d2e736f  st_filesystem.so
+ 1ad28 6c696262 6f6f7374 5f66696c 65737973  libboost_filesys
+ 1ad38 74656d2e 736f2e31 2e38312e 30006c69  tem.so.1.81.0.li
+ 1ad48 62626f6f 73745f74 68726561 642e736f  bboost_thread.so
  1ad58 2e312e38 312e3000 6c696273 7464632b  .1.81.0.libstdc+

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