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The unwind tables are in an allocated section and cannot really be removed after the final link (it would change file offsets in places that had their relocations relaxed, without a trace). These unwind tables are separate from the debugging information.

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Not after the final link, but I'm pretty sure we were using `-fdata-sections -ffunction-sections -Wl,--gc-sections`. I think that would strip any unwind section too, if it was present. Wouldn't it? Anyway, we likely didn't generate them in the first place.

No, I think -Wl,--gc-sections still produces unwind data for the functions that remain. I suppose you could use the strip command on relocatable (intermediate) .o files. But the most common approach is probably building with -fno-exceptions -fno-unwind-tables -fno-asynchronous-unwind-tables. Or perhaps the toolchain defaults to that when building C, which is an odd configuration for GNU/Linux because pthread_cancel actually uses unwinding in C (and -fexceptions avoids an unprotected function pointer on the stack that is called even on the non-canceling code path).

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