#1133557 mold: ftbfs with GCC-16

Package:
src:mold
Source:
src:mold
Submitter:
Emanuele Rocca
Date:
2026-04-13 13:08:09 UTC
Severity:
normal
Tags:
#1133557#5
Date:
2026-04-13 13:07:26 UTC
From:
To:
Hi,

mold fails to build in a test rebuild on at least amd64 and arm64 with
gcc-16/g++-16, but builds properly with gcc-15/g++-15. The severity of this
report will be raised before the forky release.

The full build log can be found at:
https://people.debian.org/~ema/gcc-16-rebuilds/output-1/mold_arm64.build.xz

The last lines of the build log are at the end of this report.

To build with GCC 16, either set CC=gcc-16 CXX=g++-16 explicitly,
or install the gcc, g++, gfortran, ... packages from experimental.

  apt-get -t=experimental install g++

Common build failures include unused (but set) variables, array subscripts
partly outside array bounds, and new/dropped symbols in Debian symbols files.
For other C/C++ related build failures see the porting guide at
http://gcc.gnu.org/gcc-16/porting_to.html

Please only close this issue after double-checking that the package can be
built correctly with GCC 16.

Please do not reassign this bug to another package. If a fix in another package
is required, then file a bug for the other package (or clone), and mark this
bug as blocked by the bug in the other package.

[...]


	302 - aarch64-tlsdesc (Failed)
	303 - aarch64-trace-symbol-symver (Failed)
	304 - aarch64-trace-symbol (Failed)
	305 - aarch64-trace (Failed)
	306 - aarch64-undefined-glob-gc-sections (Failed)
	307 - aarch64-undefined-glob (Failed)
	311 - aarch64-unresolved-symbols (Failed)
	312 - aarch64-unresolved-symbols2 (Failed)
	313 - aarch64-verbose (Failed)
	314 - aarch64-version-script-search-paths (Failed)
	315 - aarch64-version-script (Failed)
	316 - aarch64-version-script10 (Failed)
	317 - aarch64-version-script11 (Failed)
	318 - aarch64-version-script12 (Failed)
	319 - aarch64-version-script13 (Failed)
	320 - aarch64-version-script14 (Failed)
	321 - aarch64-version-script15 (Failed)
	322 - aarch64-version-script16 (Failed)
	323 - aarch64-version-script17 (Failed)
	324 - aarch64-version-script18 (Failed)
	325 - aarch64-version-script19 (Failed)
	326 - aarch64-version-script2 (Failed)
	327 - aarch64-version-script20 (Failed)
	328 - aarch64-version-script21 (Failed)
	329 - aarch64-version-script22 (Failed)
	330 - aarch64-version-script23 (Failed)
	331 - aarch64-version-script3 (Failed)
	332 - aarch64-version-script4 (Failed)
	333 - aarch64-version-script5 (Failed)
	334 - aarch64-version-script6 (Failed)
	335 - aarch64-version-script7 (Failed)
	336 - aarch64-version-script8 (Failed)
	337 - aarch64-version-script9 (Failed)
	338 - aarch64-version (Failed)
	339 - aarch64-versioned-undef (Failed)
	340 - aarch64-visibility (Failed)
	341 - aarch64-warn-common (Failed)
	342 - aarch64-warn-once (Failed)
	343 - aarch64-warn-symbol-type (Failed)
	344 - aarch64-warn-unresolved-symbols (Failed)
	345 - aarch64-weak-export-dso (Failed)
	346 - aarch64-weak-export-dso2 (Failed)
	347 - aarch64-weak-export-exe (Failed)
	348 - aarch64-weak-undef-dso (Failed)
	349 - aarch64-weak-undef (Failed)
	350 - aarch64-weak-undef2 (Failed)
	351 - aarch64-weak-undef4 (Failed)
	352 - aarch64-weak-undef5 (Failed)
	355 - aarch64-wrap (Failed)
	356 - aarch64-z-cet-report (Failed)
	357 - aarch64-z-defs (Failed)
	358 - aarch64-z-dynamic-undefined-weak-exe (Failed)
	359 - aarch64-z-dynamic-undefined-weak (Failed)
	360 - aarch64-z-dynamic-undefined-weak2 (Failed)
	361 - aarch64-z-max-page-size (Failed)
	362 - aarch64-z-nodefaultlib (Failed)
	363 - aarch64-z-nodump (Failed)
	364 - aarch64-z-now (Failed)
	365 - aarch64-z-origin (Failed)
	366 - aarch64-z-pack-relative-relocs (Failed)
	367 - aarch64-z-rodynamic (Failed)
	368 - aarch64-z-sectionheader (Failed)
	369 - aarch64-z-separate-code (Failed)
	370 - aarch64-z-stack-size (Failed)
	371 - aarch64-z-start-stop-visibility (Failed)
Errors while running CTest
make[1]: *** [Makefile:74: test] Error 8
make[1]: Leaving directory '/build/reproducible-path/mold-2.40.4+dfsg/obj-aarch64-linux-gnu'
dh_auto_test: error: cd obj-aarch64-linux-gnu && make -j128 test ARGS\+=--verbose ARGS\+=-j128 returned exit code 2
make: *** [debian/rules:16: binary] Error 25
dpkg-buildpackage: error: debian/rules binary subprocess failed with exit status 2