Bridgetest Failing on RPI4 armhf

[Stephan Bergmann]

On 23/10/2020 15:38, Luke Benes wrote:
> On Raspberry Pi OS with both gcc-8 and clang 12, the build is failing with the following error:
> 
> ### float does not match! failed
> struct comparison test failed
> ### float does not match! failed
> recursive test results failed
> standard test failed
> exception occurred: error: test failed! /core/testtools/source/bridgetest/bridgetest.cxx:1175
> 
>> error: error: test failed! /core/testtools/source/bridgetest/bridgetest.cxx:1175
>> dying...make[1]: *** [/core/testtools/CustomTarget_uno_test.mk:25: /core/workdir/CustomTarget/testtools/uno_test.done] Error 1

That's

     check( rData1.Float == rData2.Float, "### float does not match!" );

at testtools/source/bridgetest/bridgetest.cxx:134.  I'd start 
investigating by dumping out the bytes making up those two float 
objects, to see how they differ.  (Most plausible causes are either some 
snafu when comparing those floats for bitwise equality, or some ABI 
issue with passing floats around.)

> Stephan fixed a very similar issue for aarch64 here:
> https://cgit.freedesktop.org/libreoffice/core/commit/?id=7b0ab85b4042cb38221ca5c9794b70c87443181f

That "Pass -fno-lto unconditionally" looks rather unrelated.