Fails to build on many archs

[TinoDidriksen]

From Debian:

• https://bugs.debian.org/911226
• https://buildd.debian.org/status/package.php?p=lttoolbox

Fails to build/test on all ARMs, PPC, and s390x.

Maybe related to whatever #30 was.

[TinoDidriksen]

- ^cat/cat+n<W:10.178184>/cat+v<W:11.209916>$[][
+ ^cat/cat+n<W:9.353620>/cat+v<W:10.385352>$[][

- 3     4       \u03b5  +       0.000000
+ 3     4       \u03b5  +       -0.824564
- 5     0.000000
+ 5     -0.525487

Curiously, the cat difference is the same 0.82: 9.353620 - 10.178184 = 10.385352 - 11.209916 = -0.824564.

The hex representation is -0.824564 = 0xbfea62d40aaeafab, 0.824564 = 0x3fea62d40aaeafab, -0.525487 = 0xbfe0d0ca1cef2410, 0.525487 = 0x3fe0d0ca1cef2410.

[TinoDidriksen]

https://github.com/apertium/lttoolbox/blob/master/lttoolbox/compression.cc#L310 is where things go wrong.

Working archs: -0.525487 becomes 3730729927 0, and -0.824564 becomes 3409598443 0

Buggy archs: Everything negative yields 0 0

[TinoDidriksen]

@Techievena where did you get that floating point serialization code? It's quite bizarre.

[kartikm]

@TinoDidriksen Should we push this patch to Debian soon?

[TinoDidriksen]

I guess so. There are some segfaults I would've liked to fix in the same push, but they don't seem like critical blockers.