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Troubleshooting compiling Academic Signature in (x/l/k) ubuntu17.10

A workaround is already in place in the current source code packages since nov 8, 2017.

This page is about a flaw that apparently occurred in close coincidence with the rollout of ubuntu Artful Aardvark.
It only occurs in the 64 bit version of the compiler g++, the 32bit version is not affected.

As of November 2017 g++ (Ubuntu 7.2.0-8ubuntu3) 7.2.0 (64 bit version only) will produce faulty object files, if optimization -O2 or -O3 are turned on.
And it does so in Academic Signature's module helpersxx.cpp, affects the function "bool dbytadd_ay" used in some pseudorandom functions and would reproducably alter the outcome of pseudo random functions used in ciphers "flightx", "chimera" and in a key derivation function
(No, this is not about ambiguous, poorly defined code or illegal type punning. It is about a plain and simple pointer access with calculated offset.)

I can fix the flaw by either introducing an additional dummy function parameter to convince g++ that it cannot assume it would know the memory content of a particular byte (that might have been altered in the mean time) and optimizes a second access away or else I can just put in a g++ compiler pragma blocking optimization in that function. Since the first solution would marginally slow down execution I pick the latter solution. Those users who have the alternative compiler clang on their Linux (or Mingw on a Windows) may just use clang, which optimizes flawlessly for all optimization levels as far as I can see.
I have noted a very rude conversation about an alleged compiler flaw between a developer and the innocent user trying to report the bug. Thus I figured they don't want user interaction, refrained from contacting them about the bug and possibly spared me a shitstorm...