FAANGs we're deeply involved in designing LTO. See, e.g.,

https://research.google/pubs/thinlto-scalable-and-incrementa...

And other refs.

And yet...

Google also uses identical code folding. It's a pretty silly idea that a shop that big doesn't know about the compiler flags.

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Orphis 4 hours ago | parent [-]

Google is made of many thousands of individuals. Some experts will be aware of all those, some won't. In my team, many didn't know about those details as they were handled by other builds teams for specific products or entire domains at once.

But since each product in some different domains had to actively enable those optimizations for themselves, they were occasionally forgotten, and I found a few in the app I worked for (but not directly on).

	▲	jeffbee 4 hours ago \| parent [-]
		ICF seems like a good one to keep in the box of flags people don't know about because like everything in life it's a tradeoff and keeping that one problematic artifact under 2GiB is pretty much the only non-debatable use case for it.