-O3 Enabled?

vijay nag vijunag@gmail.com
Wed Aug 7 04:58:00 GMT 2013

On Wed, Aug 7, 2013 at 7:49 AM, Hei Chan <structurechart@yahoo.com> wrote:
> Hi,
> I believe my question has been asked before but my search online has no relevant result.
> Is it possible to figure whether -O3 is enabled in a static library and an executable?  I am using GCC 4.6.x.
> Thanks in advance.
> Cheers,
> Hei

If you just have the binary without the source, I guess it is
impossible to figure out optimization level.

If you have source for the same, you can build it with -O0,
disassemble the code and compare the compiler code emission for a

In future, if you would like to know the CFLAGS with which it was
built, you can export those information to a header as #define's and
be included
in one of compilation units.

Vijay Nag

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