How to detect code compiled with LTO?

Question

Exist any way to detect if code is compiled with -flto?

Example is classic library or executable under Linux compiled with GCC (4.9.1), without debugging.

Moxie

Answer 1

Considering that LTO information is stored in several ELF sections inside object files (see LTO file sections), you could try and see what readelf returns (as used for instance in this answer).

Look for .gnu.lto_.xxx entries.

Barrens

For clang, look here: #51048914 – Harmless