g++-14 performance regression - built with debug checks
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
gcc-14 (Ubuntu) |
Confirmed
|
Undecided
|
Unassigned |
Bug Description
System information (Docker container for ubuntu:24.04):
```
$> lsb_release -rd
No LSB modules are available.
Description: Ubuntu 24.04 LTS
Release: 24.04
```
Package information:
```
$> apt-cache policy g++-14
g++-14:
Installed: 14-20240412-
Candidate: 14-20240412-
Version table:
*** 14-20240412-
500 http://
100 /var/lib/
```
g++-14 in Ubuntu 24.04 builds extremely slow. At Boost, we've noticed increases of around x2 in CI build times.
This thread by some of my colleagues at Boost summarizes the problems we've found: https:/
It looks like Ubuntu 24.04 g++-14 is indeed a debug build, and hence the slowdown. Running in an `ubuntu:24.04` Docker container the following:
```
apt update
apt install -y --no-install-
g++-14 -v
```
Yields the following:
```
g++-14 -v
Using built-in specs.
COLLECT_GCC=g++-14
COLLECT_
OFFLOAD_
OFFLOAD_
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-
Thread model: posix
Supported LTO compression algorithms: zlib zstd
gcc version 14.0.1 20240412 (experimental) [master r14-9935-
```
The problem is `--enable-
Reading gcc's configure page, I think this happened because gcc was built from the master branch (as the release branch wasn't out at the time Ubuntu 24.04 was published).
Now that gcc 14 is officially out, it would be great if we could get an updated package with gcc built in release mode.
Thanks,
Ruben.
affects: | ubuntu → gcc-14 (Ubuntu) |
tags: | added: noble |
tags: | added: release-oo-incoming |
Status changed to 'Confirmed' because the bug affects multiple users.