recent KahanSum change causes a new test failure on ppc64le

[Stephan Bergmann]

On 9/5/23 18:53, Dan Horák wrote:
> seems the recent change [1] to KahanSum handling causes a test failure
> on ppc64le.
> 
> Running scope as unit: -home-sharkcz-projects-libreoffice-workdir-CppunitTest-sc_statistical_functions_test.test:20230905152639:2378561.scope
> [_RUN_____] StatisticalFunctionsTest::testStatisticalFormulasFODS
> Testing load file:///home/sharkcz/projects/libreoffice//sc/qa/unit/data/functions/statistical/fods/KahanSum.fods:
> /home/sharkcz/projects/libreoffice/sc/qa/unit/functions_test.cxx:49:StatisticalFunctionsTest::testStatisticalFormulasFODS
> forced failure
> - Testing file:///home/sharkcz/projects/libreoffice//sc/qa/unit/data/functions/statistical/fods/KahanSum.fods failed, Sheet2.A90 '=SUM(F3:F102)' result: 6.6, expected: 5

Interesting; I also saw that failure with my latest local build on macOS 
aarch64 against Clang trunk.  (But didn't debug it further and wrote it 
off as maybe some intermittent Clang trunk bug.)