disable CFI in the cross compiler to drop the unused .eh_frame - #182
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samoht wants to merge 1 commit into
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disable CFI in the cross compiler to drop the unused .eh_frame#182samoht wants to merge 1 commit into
samoht wants to merge 1 commit into
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OCaml's native exceptions unwind through its own trap stack, not DWARF, so the CFI the compiler emits ends up as a ~0.5 MiB .eh_frame that the unikernel never reads. It is SHF_ALLOC in a PT_LOAD segment, so strip cannot reclaim it. Configure the cross compiler with --disable-cfi so it is never emitted.
samoht
marked this pull request as draft
July 10, 2026 21:06
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OCaml native exceptions unwind through their own trap stack rather than DWARF, so the CFI the compiler emits is dead weight in a unikernel: a ~0.5 MiB
.eh_framethat nothing ever reads. Because it isSHF_ALLOCin aPT_LOADsegment,stripcannot reclaim it either.This builds the cross compiler with
--disable-cfi, soocamloptnever emits the.cfi_*directives in the first place and the section disappears from the target objects and the final image.