Package: chromium
Version: 111.0.5563.64-1
Severity: minor
I've been experimenting with building the latest Debian chromium package
on Ubuntu 22.04, and in the course of that have found a couple of minor
issues in the debian/rules file:
* The flags added by optimize=+lto in DEB_BUILD_MAINT_OPTIONS will
cause every compile invocation to print "optimization flag
'-ffat-lto-objects' is not supported" warnings (as the dpkg LTO flags
are meant for GCC, not Clang), and balloon the RAM required for the
final link from ~2.5 GB to ~30 GB. The link will also require much
more time to complete; on my fairly beefy test system, it went from
under a minute to four hours.
Disabling this explicitly before Debian enables LTO system-wide would
be a good move, in my view. On Ubuntu, LTO is already the default, and
without adding this bit, the package is difficult to build in their
infrastructure due to the resource requirements.
* LDFLAGS is set without obtaining an initial value from
dpkg-buildflags(1).
The attached patch addresses both issues.
Side note: You may want to consider enabling ThinLTO, by setting
use_thin_lto=true and unsetting concurrent_links. The final link
requires only ~10.5 GB RAM, and completes within minutes.
--Daniel
--
Daniel Richard G. || sk...@iskunk.org
My ASCII-art .sig got a bad case of Times New Roman.
--- chromium-111.0.5563.64/debian/rules.orig 2023-03-02 01:24:58.000000000 +0000
+++ chromium-111.0.5563.64/debian/rules 2023-03-15 08:15:54.485885154 +0000
@@ -6,6 +6,9 @@
# enable all build hardening flags
export DEB_BUILD_MAINT_OPTIONS=hardening=+all
+# disable lto flags, as they are for gcc, not clang
+export DEB_BUILD_MAINT_OPTIONS+=optimize=-lto
+
# indicate that binary targets do not require root
export DEB_RULES_REQUIRES_ROOT=no
@@ -15,12 +18,13 @@
export CC=clang
export CXX=clang++
-# more verbose linker output
-export LDFLAGS+=-Wl,--stats
-
# initial flags from dpkg-buildflags
export DEB_CXXFLAGS_MAINT_STRIP=-g
export CXXFLAGS=$(shell dpkg-buildflags --get CXXFLAGS)
+export LDFLAGS=$(shell dpkg-buildflags --get LDFLAGS)
+
+# more verbose linker output
+export LDFLAGS+=-Wl,--stats
# extra flags to reduce warnings that aren't very useful
export CXXFLAGS+=-Wno-conversion \
