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Changes between Initial Version and Version 1 of Ticket #69573, comment 5

initial	v1
3	3
4	4	It is not clear to me whether this was intended and not just a copy-paste from x86 case; normally, host `powerpc64` == `ppc64`.
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	6	P. S. GCC has some obscure optimizations allowing for specific 64-bit insns to be emulated on G5 running in 32-bit mode (I may not describe it accurately, saying from memory), but those are pretty unsafe and, I believe, we rather not use those. Other than that, what is the use-case for recording powerpc64 for a powerpc(32) build/host?
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	8	(I recall Intel had an issue where x86_64 build could be forced into 32-bit (`mlton` had that issue, for example), so this hack could be addressing those.)