bazelbuild
broken result files when linking with _ld.gold_ is interrupted
Description of the problem
When I interrupt a link step of a C++ project, I get a result of in bazel-bin that has got the correct size but contains only nul bytes.
How To Reproduce The Problem
- set up a C++ project with lots of
cc_binaryrules - make sure your toolchain uses ld.gold (
-fuse-ld=gold) - start the build with
bazel build --experimental_use_sandboxfs - press Ctrl-C
- look for files filled with nul bytes
find bazel-bin/ -xtype f -size +0 -exec grep --text --files-without-match -P '[^\0]' {} + -ls
The problem also occurs when a build error occurs and Bazel interrupts currently running linking steps on its own (if you don't use --keep_going).
Environment
RHEL 7.4: Linux 3.10.0, CPU with four cores + HT, using devtool-10 (devtoolset-10-binutils-2.35-3.el7.x86_64).
SW Version
bazel 4.1.0 sandboxfs 0.2.0
Further Observations
ld.gold does not seem to make any effort to prevent broken output files if it gets killed: https://sourceware.org/bugzilla/show_bug.cgi?id=27972
The problem does not occur with GNU ld. GNU ld deletes unfinished output filse in an atexit handler.
Does sandboxfs only check for the existance of the output files and ignore the exit value of ld.gold?
