On 05/06/12 00:21, Paul Hartman wrote:
On Mon, Jun 4, 2012 at 3:19 PM, Nikos Chantziaras<rea...@gmail.com> wrote:
I've emerged system and world with gcc-4.7.0 and LTO. I'm posting from it
right now :-) It's a KDE system with 1043 packages installed.
I've posted details on how to do this (including info on how to disable LTO
for specific packages that don't work with it) here:
http://realnc.blogspot.com/2012/06/building-gentoo-linux-with-gcc-47-and.html
[...]
Do you have any measure of compile times using lto compared to not using it?
It was pretty obvious without doing any actual measurement: linking is
slower with LTO. Large programs even take several minutes for the link
step.
Was there any effect on quality of debugging info in the resulting
binaries? I thought I read at some point there was no (or bad) debug
info with LTO. Maybe I'm thinking about clang, though.
Didn't notice anything strange yet. But I suspect that this isn't
important to begin with; all we need are backtraces. Thorough debugging
symbols are not important for emerged packages.
Did you use gold or the standard linker?
The standard one. I didn't actually think about the importance of this.
Does gold work better with LTO?
