gcc 4.1 -O1 problem

John Love-Jensen eljay@adobe.com
Thu Mar 16 12:50:00 GMT 2006

Hi Kevin,

I think your code is correct, and the GCC 4.1 compiler has a boo-boo.  File
a bug report, please, including the code snippet that reproduces the
suspected bug, what platform, and the command line used to compile the code.
See "Bugs" section on the left column of <http://gcc.gnu.org/>.

Anyway, here's a couple bits of tid (as I understand it):

-O0 disables all optimizations.  The -fenable-something likely don't enable
the specified optimization when -O0 is specified (if there are exceptions,
I'm not aware of them).

-fverbose-asm (with -S or -save-temps) is useful to ascertain what
optimizations are happenings with -O1, -O2, -O3, -Os.

As I understand it, only select optimizations are twiddlible with -f flags,
but not all of the possible optimizations.


PS:  twiddlible ... *heh*

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