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Also putting a note in vmlinux >>> to indicate whether lto is enabled for built or not can >>> provide a much faster way. >>> >>> This patch set implemented this two approaches, first >>> checking the note (in Patch #2), if not found, then >>> check .debug_abbrev (in Patch #1). >>> >>> Yonghong Song (2): >>> dwarf_loader: check .debug_abbrev for cross-cu references >>> dwarf_loader: check .notes section for lto build info >>> >>> dwarf_loader.c | 76 ++++++++++++++++++++++++++++++++++++-------------- >>> 1 file changed, 55 insertions(+), 21 deletions(-) >>> >> With this series of patches, the compilation passes for me with >> ThinLTO. You may add this if you like: >> >> Tested-by: Bill Wendling > > I did notice these warnings following the "pahole -J .tmp_vmlinux.btf" > command. I don't know the severity of them, but it might be good to > investigate. > > $ ./tools/bpf/resolve_btfids/resolve_btfids vmlinux > BTFIDS vmlinux > WARN: multiple IDs found for 'inode': 355, 8746 - using 355 > WARN: multiple IDs found for 'file': 588, 8779 - using 588 > WARN: multiple IDs found for 'path': 411, 8780 - using 411 > WARN: multiple IDs found for 'seq_file': 1414, 8836 - using 1414 > WARN: multiple IDs found for 'vm_area_struct': 538, 8873 - using 538 > WARN: multiple IDs found for 'task_struct': 28, 8880 - using 28 > WARN: multiple IDs found for 'inode': 355, 9484 - using 355 > WARN: multiple IDs found for 'file': 588, 9517 - using 588 > WARN: multiple IDs found for 'path': 411, 9518 - using 411 > WARN: multiple IDs found for 'seq_file': 1414, 9578 - using 1414 > WARN: multiple IDs found for 'vm_area_struct': 538, 9615 - using 538 > WARN: multiple IDs found for 'task_struct': 28, 9622 - using 28 > WARN: multiple IDs found for 'seq_file': 1414, 12223 - using 1414 > WARN: multiple IDs found for 'file': 588, 12237 - using 588 > WARN: multiple IDs found for 'path': 411, 12238 - using 411 > ... I didn't see it with my config. Maybe you can share your config file? > > -bw >