print gcc optimization log

[Xin Tong]

are these options enabled on production build, i.e. build i install
with apt-get install gcc on ubuntu ?

Xin


On Wed, Aug 15, 2012 at 10:21 PM, Ian Lance Taylor <iant@google.com> wrote:
> On Wed, Aug 15, 2012 at 8:58 PM, Xin Tong <xerox.time.tech@gmail.com> wrote:
>> I sometimes run into issues where i want to figure out why gcc is
>> performing a specific optimization and what the optimization affects
>> the tree. is there any documents on how to print gcc optimizations and
>> code generation logs ?
>
> Unfortunately GCC has very little in the way of logs intended for end
> users.  About all I know is the -ftree-vectorizer-verbose information,
> which gives useful feedback about the vectorization optimizations.
>
> You can a lot of information by  using -fdump-tree-all-details
> -fdump-rtl-all-details, but it's difficult to interpret without the
> source code and a working knowledge of GCC internals.
>
> Ian